Ash Barty moved a step closer to a second Adelaide International title in three seasons as she crushed defending champion Iga Swiatek's hopes in the semi-finals.

Competing as a stepping stone towards her principal goal of challenging for the Australian Open title later in the month, home favourite Barty sped to a 6-2 6-4 win over the 2020 French Open winner.

She served fewer aces than Swiatek – five to the seven fired down by the 20-year-old Pole – but Barty's powerful forehand proved decisive as she made snappy work of ending the contest.

Barty will face Elena Rybakina in Sunday's final, after the Kazakh beat Japan's Misaki Doi 6-4 6-3. Queenslander Barty beat Dayana Yastremska in the 2020 final.

Having won the French Open and Wimbledon already in her career, Barty will be the favourite at the Australian Open, which begins on January 17 in Melbourne.

The world number one, by seeing off ninth-ranked Swiatek, boosted her win-loss record against top-10 WTA rivals to 8-1 since the beginning of last year.

Barty said, quoted on the WTA website: "It is exciting to be able to play well here in Australia. This is where I want to play my best tennis. I want to give myself an opportunity to play for titles in Australia.

"It's something really exciting to start the year off as an Aussie player in front of our home fans."

Reflecting on a positive performance, Barty, who has also reached the doubles final with Storm Sanders, said: "I felt like on Iga's service games I was able to get into most of them, which is important when you're playing someone who can dominate with that first ball and first strike.

"I felt like I was able to build pressure over time, making her play a lot of balls on her service games, not giving her too many cheapies."

Swiatek is entered into next week's Sydney Classic and learned on Saturday that she faces a testing opener there, having been drawn to face Great Britain's US Open champion Emma Raducanu in a standout first-round match.

At the Melbourne Summer Set 2 tournament, Russian third seed Daria Kasatkina suffered a shock 6-2 6-0 semi-final defeat at the hands of American world number 78 Amanda Anisimova.

Anisimova goes on to face fellow unseeded player Aliaksandra Sasnovich for the title, after the Belarusian beat American Ann Li 7-6 (7-4) 2-6 6-3.

Ash Barty set a new personal best for aces in a match as she rifled 17 past Sofia Kenin on the way through to the Adelaide International 1 semi-finals.

Reigning Wimbledon champion Barty won 31 of 32 points on first serve in a ruthless 6-3 6-4 victory over the 2020 Australian Open winner.

It sets up a tantalising last-four clash with Poland's defending champion Iga Swiatek, who is a frequent practice partner for Australian home favourite Barty.

Explaining her stunning serving performance, Barty said: "I think towards the end Sofia was kind of leaning one way or the other, and I was able to kind of get up and hit my spots."

Facing former French Open winner Swiatek will be a major early-season test for the world number one, with the Warsaw-born 20-year-old fending off former grand slam winner Victoria Azarenka 6-3 2-6 6-1 in Friday's quarter-final.

The other semi-final in Adelaide will see Misaki Doi take on Elena Rybakina after both won in three sets to get there, seeing off Kaja Juvan and Shelby Rogers respectively.

Melbourne Park is staging two tournaments this week, and there is the prospect of a starry final in Melbourne Summer Set 1, with Naomi Osaka and Simona Halep both through to the last four.

Top seed Osaka beat experienced German Andrea Petkovic 6-1 7-5, while second seed Halep had to scrap for a 6-2 5-7 6-4 win against Viktorija Golubic of Switzerland.

Osaka took inspiration from Petkovic's fight in the second set of their contest. Quoted on the tournament website, she said: "It was really cool how she didn't give up for any point, so I just felt like I should do the same thing and see what happens."

Halep said her encounter with Golubic had been "really difficult", adding: "I didn't really trust that I can win this match, but I fought to the end, and I'm very proud of this."

Saturday's semi-finals of Melbourne Summer Set 2 will seed Daria Kasatkina take on Amanda Anisimova, while Ann Li plays Aliaksandra Sasnovich.

World number one Ash Barty will start her 2022 season at the Adelaide International along with eight of the other current 10 top players in the world.

Barty has held top spot in the women's rankings since September 2019 and collected five titles – including Wimbledon – in the 2021 season but missed the French Open with a hip injury.

She also opted to not play in the season-ending WTA Finals in Mexico due to coronavirus-enforced quarantine concerns that could disrupt her preparation for the following campaign.

The Women's Tennis Association (WTA) confirmed on Friday that Barty would begin her 2022 season in Adelaide on January 2, along with defending champion Iga Swiatek, WTA Finals victor Garbine Muguruza and Roland Garros winner Barbora Krejcikova, as the world's elite players prepare for the Australian Open.

The entry list for the WTA 500 tournaments also includes Tokyo Olympics gold medallist Barbara Bencic, who finished runner-up to Swiatek in 2021, former world number one Karolina Pliskova and US Open runner-up Leylah Fernandez.

The field boasts 12 major trophies between them, but three grand slam winners will kick-start their seasons in Melbourne the day after.

Naomi Osaka, who is aiming to defend her title at the Australian Open, gets her preparations underway in the Melbourne Summer Set.

Two-time major winner Simona Halep and reigning US Open champion Emma Raducanu will play in the Melbourne Summer Set.

The trio are among 20 of the top 50 ranked players in the world for the two WTA 250 tournaments starting on January 3, with the entry list split between the competitions the week before matches start.

Raducanu will feature in just her eighth Tour-level event, and her fourth tournament since winning her first major, while Osaka will be appearing for the first time since an early defeat in the third round of the US Open to Fernandez.

Paula Badosa's winning start at the WTA Finals came to an end as she prepared for her semi-final with a straight-sets defeat to Iga Swiatek in a group-stage dead rubber.

Badosa, playing on her 24th birthday, was already assured of a last-four meeting with fellow Spaniard Garbine Muguruza, while two defeats had seen Swiatek eliminated.

A low-stakes encounter allowed both women to play with a little freedom, although Swiatek was a deserving 7-5 6-4 winner.

The pair traded early breaks in the opener, with Badosa immediately ceding her initial lead and finding herself on the back foot for the remainder of the set.

The semi-finalist survived a set point on her serve at 5-4 but had no answer when Swiatek went on the offensive again two games later, stepping forward with a stunning backhand to create her opportunity before retreating to the back of the court to put her forehand to good use and leave Badosa rooted once more.

Badosa again broke first in the second and this time looked to have control when she fought off seven break points to this time consolidate her lead in a gripping 12-minute game.

But Swiatek would not relent, breaking at the first attempt next time with powerful hitting from the centre of the court. Then a wayward Badosa backhand teed up match point for the 20-year-old, whose smart return completed the job.

WINNERS/UNFORCED ERRORS 

Swiatek– 16/20
Badosa – 18/33

ACES/DOUBLE FAULTS 

Swiatek – 0/3
Badosa– 5/5

BREAK POINTS WON 

Swiatek – 4/13
Badosa – 2/2

Top seed Aryna Sabalenka bounced back from a disappointing defeat in her opening match at the WTA Finals to rally past Iga Swiatek in Guadalajara. 

Sabalenka steadied herself after dropping the opening set and prevailed 2-6 6-2 7-5 Saturday to keep alive her hopes of reaching the semi-finals in her maiden appearance at the event. 

Swiatek, the youngest player in the field at age 20, broke Sabalenka in her final two service games of the first set but could not maintain the momentum as the Belarusian returned the favour in the second. 

Sabalenka entered Saturday with a 9-13 record in three-set matches compared to 35-4 in two-setters but maintained her nerve after the pair traded breaks early in the decider. 

The world number two broke Swiatek to take a 6-5 lead, then served the final game out at love for the victory. 

With Sabalenka's win, Paula Badosa advances to the semi-finals as winner of the group, while the winner of Monday's match between Sabalenka and Maria Sakkari also will advance. Swiatek is out of contention for the semis. 

History is not necessarily on Sabalenka's side, as the top seed has failed to advance from the group stage at three of the past five WTA Finals. 

WINNERS/UNFORCED ERRORS 

Sabalenka – 16/27
Swiatek – 15/18

ACES/DOUBLE FAULTS 

Sabalenka – 8/16
Swiatek – 2/3

BREAK POINTS WON 

Sabalenka – 4/7
Swiatek – 3/7

Maria Sakkari was merciless as she began her WTA Finals campaign with a comfortable 6-2 6-4 win over an Iga Swiatek who became visibly emotional towards the end.

It was Sakkari's eighth win over a top-10 opponent this season, the most of any player on the WTA Tour, while the victory took her to 3-0 against Swiatek this year.

Sakkari, with her trademark intensity and feistiness, appeared to adjust to the conditions and altitude of Guadalajara much better than her opponent, who looked lethargic during the first set.

This was particularly evident in the 20-year-old's second service game, as Sakkari converted the second of her break points to get the early advantage.

Swiatek showed the occasional flash of quality, such as an awesome out-of-the-blue cross-court forehand in the fifth game, but she soon found herself 5-2 down as Sakkari broke to love, the decisive point gifted to her by a sloppy volley at the net that the Pole inexplicably put beyond the sideline.

Sakkari quickly wrapped up the set but Swiatek was able to dig a bit deeper in the second, showing great determination to eventually hold serve during the 10-minute third game.

But her body language at the change was hardly indicative of a player convinced she could level the match, as she sat there with a towel draped over her from head to knees.

Swiatek held out for another few games but Sakkari got the decisive break to go 4-3 up, and the match ultimately went with serve from there.

Sakkari finished her opponent off by serving to love, with a tearful Swiatek given a code violation for turning her back as she attempted to regain her composure before facing triple match point, ultimately putting her return into the net.

WINNERS/UNFORCED ERRORS

Sakkari – 15/22
Swiatek – 8/29

ACES/DOUBLE FAULTS

Sakkari – 2/5
Swiatek – 2/6

BREAK POINTS WON

Sakkari – 3/8
Swiatek – 0/2

The 2021 WTA Finals look set to be a fitting end to a fascinating season on the Tour.

The 50th year-ending championships, which will take place in Guadalajara instead of Shenzhen due to coronavirus restrictions, will see eight of the top-10 ranked players come together in two round-robin groups, with four semi-final places up for grabs.

Six of the eight competitors will make their debuts at the event, while only two grand slam finalists from this year – and just one champion – will be present. With world number one Ash Barty withdrawing because of concerns around possible quarantine issues, it really does feel like an open draw.

Stats Perform looks at the eight Finalists and the key data you need to know before the action gets underway...

Group Chichen Itza

Aryna Sabalenka (1)

World number two Sabalenka is the top-ranked competitor in Guadalajara, with 44 match wins this year and titles in Abu Dhabi and Madrid, where she beat Barty.

The Belarusian boasts formidable weapons: Sabalenka has won 71.1 per cent of first-serve points and has an average of 8.4 forehand winners per match on the Tour this season, both of which are best figures among the eight Finalists.

She has only played two matches since losing to Leylah Fernandez in the US Open semi-finals, though, both of which were at last month's Kremlin Cup in Moscow.

Did you know? Since the start of 2018, Sabalenka has won the joint-most matches (three) in WTA Tour main draws after losing the first set 0-6. At the same time, she is 9-13 in three-set contests in 2021.

Maria Sakkari (4)

The nearly-woman of 2021, Sakkari has reached more semi-finals this year (seven) than anyone else on the WTA Tour, including at two of the four slams, but made it to just one final (in Ostrava, where she lost to Anett Kontaveit).

Still, this has been a historic year for the 26-year-old, who became the first Greek woman to reach a major semi-final, enter the top 10 and qualify for the season-ending championship.

Since the start of the US Open, Sakkari has lost only four of 14 matches, a run that includes the semi-final of the Kremlin Cup where she retired due to dizziness.

Did you know? Nobody has won more Tour-level matches against top-10 opponents this year than Sakkari (seven, level with Barty and Jessica Pegula). Before 2021, her record in such matches was 10-13.

Iga Swiatek (5)

Swiatek, the 2020 French Open champion, is the youngest competitor at these Finals at 20 years and 170 days old (as of the tournament's end). She is just the second player born this century to reach this event, after Bianca Andreescu in 2019.

Although unable to get beyond the quarter-finals of a major this year, Swiatek did win titles in Adelaide and Rome, where she inflicted a double bagel on Karolina Pliskova in the final.

Her success in Australia was her first on a hard court, a surface on which she won 19 of 28 matches this year.

Did you know? Swiatek has won 58 per cent (28 of 48) of her matches this season in straight sets, the highest ratio among the Finalists.

Paula Badosa (7)

A successful year for Badosa has been built on clay: she won a Tour-leading 17 matches on the dirt in 2021, reaching the French Open quarter-finals, the last four in Madrid and Charleston and winning the title in Belgrade.

This has been a breakthrough season for the 23-year-old across all surfaces, though, one that culminated in a record-breaking three-set win over Victoria Azarenka in the final at Indian Wells last month.

Badosa clinched that match after a third-set tie-break. She has won four deciding sets in that fashion this year, the most of anyone on the WTA Tour.

Did you know? Badosa has won seven matches (excluding the Olympics) after dropping the first set in 2021. Nobody else has as many come-from-behind victories among the Finalists.

Group Teotihuacan

Barbora Krejcikova (2)

The only major singles champion from 2021 at these Finals, Krejcikova has enjoyed a remarkable rise this year.

Along with success at Roland Garros, where she also triumphed in the doubles, the Czech won titles in Strasbourg and Prague; only world number one Barty (five) and Kontaveit (four) have won more this year.

Among the eight finalists, Krejcikova boasts the highest break-point conversion ratio (49.7 per cent, or 142/286) and break-point saved figure (66.4 per cent, or 150/226) for this season. She has become a clutch competitor and will be hard to stop in Mexico, both in the singles and the doubles.

Did you know? Krejcikova has won six matches against top-20 opponents in her career. All six of those wins were in 2021.

Karolina Pliskova (3)

Pliskova boasts impressive experience of the year-ending event: she is only the fourth player to qualify for five or more WTA Finals since the current format was introduced in 2003 (after Agnieszka Radwanska, Petra Kvitova and Azarenka).

Beaten in her three Tour finals this year, including Wimbledon, the 29-year-old will be desperate to go at least one better than her three consecutive semi-final appearances at this event.

Pliskova begins against Garbine Muguruza, a player she has beaten twice before at the season-ending tournament.

Did you know? Pliskova leads the Tour for aces this season with 364, hitting a year-best 21 in her round-of-16 match with Jelena Ostapenko in Stuttgart. It's the fourth time in the past six seasons Pliskova has been top of the aces standings.

Garbine Muguruza (6)

This is the first time since 2000 that two Spanish players have contested the Finals. Back then, it was Conchita Martinez and Arantxa Sanchez Vicario at Madison Square Garden in New York.

Muguruza, champion in Dubai and Chicago this year, has won more matches on hard courts (34) than anyone else in 2021 aside from Kontaveit. She also boasts the best average for successful net approaches this year (3.0) among the Finalists, which will make her a challenging obstacle in what will be her first Finals since 2017.

The former world number won made a career-high four Tour finals this year and won more than one trophy in a season for just the second time, sending her back into the top 10 for the first time since 2018. 

Did you know? Muguruza boasts a 10-1 record in WTA tournaments in Mexico, winning back-to-back titles in Monterrey in 2018 and 2019.

Anett Kontaveit (8)

With a Tour-leading 37 hard-court wins this year and on a formidable run of form, Kontaveit could spring a surprise at her first Finals.

After losing her fifth match in a row to Ons Jabeur on August 17, the Estonian went on a run of 26 wins from 28 matches, lifted four titles and broke into the top 10 for the first time. It was Jabeur she edged out for a place at this tournament after she won her fourth title of the year at Cluj-Napoca.

Along with Barty, Kontaveit is the only player to reach six Tour-level finals this year, while nobody at the season-ending tournament has won more titles (four).

Did you know? Kontaveit has hit the most backhand winners (293) on hard courts on the WTA Tour in 2021, averaging nearly six per match.

Iga Swiatek was knocked out of the Indian Wells Open in the round of 16, the second seed headlining the list of casualties on Tuesday.

Swiatek was swept aside by Jelena Ostapenko in the battle between two previous French Open champions in the desert.

Elina Svitolina, reigning Roland Garros champion Barbora Krejcikova and US Open runner-up Leylah Fernandez were also sent packing from the WTA Premier 1000 event.

SWIATEK CRUMBLES

After top seed Karolina Pliskova was eliminated on Monday, 2020 French Open champion Swiatek crashed out following a 6-4 6-3 defeat to Ostapenko.

Ostapenko – the 2017 Roland Garros winner – rallied from a break down in each set to reach the quarter-finals at Indian Wells, where the 24th seed hit 25 winners to 21 unforced errors in 93 minutes.

"I knew it was going to be a very tough match because she's such a great player, she won a grand slam and she's playing great tennis," Ostapenko said.

Standing in the way of Ostapenko and the semi-finals is Shelby Rodgers, who edged Flushing Meadows finalist Fernandez 2-6 6-1 7-6 (7-4).

SVITOLINA UPSTAGED BY PEGULA

Svitolina's campaign in the desert did not go according to plan, the fourth seed crushed 6-1 6-1 by Jessica Pegula.

Pegula – the 2021 Australian Open quarter-finalist – dismantled Svitolina in just 68 minutes for her seventh last-eight appearance of the season and fourth at WTA 1000 level.

"I think I've just been making a lot of really good decisions in the right moments," said Pegula, who will face two-time grand slam champion Victoria Azarenka following her seventh top-10 victory. "That obviously comes with playing a lot of matches, winning and getting confidence... it's just been more belief that I can play at this level. I think this year, I realised that, and I've been having good results."

KERBER POWERS THROUGH AS KREJCIKOVA FALLS

Three-time major winner and 10th seed Kerber will feature in the quarter-finals after overpowering Ajla Tomljanovic 6-4 6-1.

Kerber will next meet 21st seed Paula Badosa, who shocked third seed and reigning French Open champion Krejcikova 6-1 7-5.

"I think I played a pretty good match today," Badosa said. "I knew I had to play on a high level against Barbora. She's an amazing player, very talented. We played before so I knew what I was going to find there on court. I'm feeling good and I'm very happy that I could play my best today."

Elina Svitolina required a third-set tie-break to progress at the Indian Wells Open, while former world number one Victoria Azarenka handled an old rival in straight sets and Simona Halep fell victim to an upset. 

Svitolina – the fourth seed – dropped the first set to 32nd seed Sorana Cirstea before fighting back to reach the round of 16 at the WTA Premier 1000 event on Sunday.

Two-time grand-slam champion Azarenka joined Svitolina in the next round after knocking out seventh seed Petra Kvitova, but 11th seed Halep became Aliaksandra Sasnovich's latest conquest. 

SVITOLINA SURVIVES CIRSTEA SCARE

Svitolina needed two hours, 32 minutes to outlast Cirstea 4-6 6-4 7-6 (7-3) and remain unbeaten in three career matches against the Romanian. 

The Ukrainian was on the defensive throughout the opening set, facing 11 break points on her serve and managing to save eight of them before Cirstea finally won out. 

Svitolina tightened things up from there, saving four of five break points the rest of the match. 

"It was a very tough match today, and I was fighting and trying to find my game," said Svitolina, who will face Jessica Pegula next. "It was a bit of a rollercoaster.

"I wish I could play a little bit better in the first set, I had chances to grab that set, but unfortunately it didn't play the way I wanted. I had to fight for every point, and Sorana played a great match, I think. I'm happy that I could win today."

AZARENKA TAKES DOWN KVITOVA

Azarenka won her first two Tour-level matches against Kvitova in 2008 and 2009 but had prevailed only once in six meetings since then before Sunday's 7-5 6-4 triumph. 

The two-time Indian Wells champion converted break-point chances when she needed them, six of 11 in all, and had 18 unforced errors to Kvitova's 26. 

"It was important to just stay there, really take my opportunities, not to let her," Azarenka said after taking down two-time Wimbledon winner Kvitova. "If she gets in the groove in couple points, not to kind of let her extend that streak, if you want to call it that.

"I was trying to still create opportunities for myself, be more aggressive, and honestly just believing also that what I'm doing is right and see how I can execute that. So intention was good. Execution followed after."

ANOTHER UPSET FOR SASNOVICH

After knocking off US Open champion Emma Raducanu in the second round, Sasnovich ushered out another grand slam winner in Halep 7-5 6-4 and will next face Azarenka.

The world number 100 had 22 winners to 16 for Halep and won 61.8 per cent of points on her serve as she reached the round of 16 at Indian Wells for the first time. 

In other matches Sunday, ninth seed Anastasia Pavlyuchenkova fell to 23rd seed and US Open runner-up Leylah Fernandez 5-7 6-3 6-4, while second seed Iga Swiatek dropped only one game in a 6-1 6-0 demolition of Veronika Kudermetova. 

Jelena Ostapenko and Shelby Rogers also advanced. 

US Open champion Emma Raducanu was sensationally beaten in her first match following her Flushing Meadows triumph, going down in straight sets to Aliaksandra Sasnovich at the Indian Wells Open on Friday.

The Belarussian, who is currently ranked 100th, stunned the 19-year-old Briton 6-2 6-4 in one hour and 25 minutes.

Raducanu had been on a 10-match winning streak coming into her maiden Indian Wells campaign.

"I'm still so new to everything. The experiences that I'm going through right now, even though I might not feel 100 per cent amazing right now, I know they're for the greater good," Raducanu said after the defeat.

"I mean, I'm 18 years old. I need to cut myself some slack."

Raducanu, who did not drop a set during her US Open run, appeared in control early after winning the opening six points, but Sasnovich claimed the first break in the third game.

Unforced errors proved costly for Raducanu as the clean-striking Sasnovich capitalized to win the first set, before opening the second set with another break.

Raducanu responded with an immediate break back and led 4-2 in the second set, before the Belarussian hit back by winning the next four games to topple the British teenager.

"It was a really good match for me. I play really well," Sasnovich said. "I know she just won US Open. I lost there in the first round. But I tried to go on court, I tried to enjoy. I did everything right."

FORMER WINNER HALEP PROGRESSES

Sasnovich will face two-time Grand Slam winner Simona Halep in the third round after the Romanian defeated Marta Kostyuk 7-6 (7-2) 6-1 in one hour and 33 minutes.

The 11th seed, who split with long-time coach Darren Cahill last month amid an injury-disrupted year, was down a break early before working her way back and dominating the tiebreak.

Halep broke twice in a more controlled second set to claim victory in her 10th appearance at Indian Wells.

"I missed a lot playing tennis at this level this year because I've been injured and many months, I couldn't play matches," said Halep, who won at Indian Wells in 2015. "I came here a little more aggressive than normal and I'm trying to improve my game and myself."

KVITOVA CRUISES AS TOP SEEDS WIN

Two-time major winner Petra Kvitova eased into the last 32 with a 6-2 6-2 triumph over Arantxa Rus from the Netherlands.

Seventh seed Kvitova set up a showdown with two-time Australian Open champion Victoria Azarenka after she beat Magda Linette 7-5 3-0 in a walkover. Kvitova leads Azarenka 5-3 in head-to-head battles.

Second seed Iga Swiatek dominated Croatian Petra Martic 6-1 6-3 to seal her passage into the third round, while fourth seed Elina Svitolina got past Teresa Martincova 6-2 7-5.

Beaten 2021 US Open finalist Leylah Fernandez triumphed over experienced Frenchwoman Alize Cornet 6-2 6-3 and will play ninth seed Anastasia Pavlyuchenkova in the third round after she easily accounted for Madison Keys 6-3 6-1.

Anett Kontaveit beat Olympic champion Belinda Bencic and will face home favourite Petra Kvitova for a place in the Ostrava Open final.

Estonian Kontaveit, ranked 30th in the world, claimed her fourth top-20 win of the season as she prevailed 6-4 6-3 on Friday.

Kontaveit also defeated Bencic in the 2020 Australian Open, meaning she is 2-0 in their head-to-head rivalry.

Czech left-hander Kvitova awaits in the last four, after the second seed defeated Bencic's Swiss compatriot Jil Teichmann 6-4 6-4.

Teichmann beat Kvitova in their only previous meeting, but the world number 10 had too much on this occasion, along with the backing of the crowd to boot as she chases a 29th singles title of her career.

The other semi-final will see top seed Iga Swiatek face Maria Sakkari.

Last year's French Open winner Swiatek reached her first semi-final since May – when she landed the prestigious title in Rome – by overcoming Elena Rybakina 7-6 (7-5) 6-2.

Sakkari, meanwhile, ended Tereza Martincova's hopes in straight sets.

Greek star Sakkari ended Swiatek's reign as Roland Garros champion in June, beating the Polish 20-year-old in the quarter-finals in Paris.

Iga Swiatek coasted through to the quarter-finals of the Ostrava Open after defeating Yulia Putintseva as Paula Badosa faltered against Anett Kontaveit.

Favourite Swiatek provided an astute performance to ease past Putintseva 6-4 6-4 to secure a potential quarter-final tie with Elena Rybakina.

Petra Kvitova, who is second seed in Croatia, did not enjoy as comfortable a victory but battled past Anastasia Potapova 6-1 6-7 (4-7) 6-3 to confirm her last-eight berth.

The ninth ranked Badosa, however, was not as fortunate as she was dumped out by Kontaveit, who cruised to a 6-3 6-4 win over the world number 27 in just over an hour.

Jelena Ostapenko set up a last-16 clash with fourth seed Maria Sakkari as she defeated Anna Blinkova 6-4 6-0, while Alison Riske recovered from a second-set setback to defeat Fiona Ferro 6-4 1-6 6-4.

Riske will now meet Jil Teichmann, who shocked former world number one Angelique Kerber, and whoever wins will be rewarded with a tie against world number 10 Kvitova.

Naomi Osaka is taking things "one notch at a time" at Tokyo 2020 after another convincing performance in round two on Monday.

With Ash Barty having suffered a shock exit a day prior, Osaka is now the favourite for glory on home court and with Aryna Sabalenka and Iga Swiatek among the round-two casualties that status is sure to only be enhanced.

There was better news for Elina Svitolina and Karolina Pliskova at the Ariake Tennis Park, though, in a women's draw stacked with top-tier talent.

OSAKA NOT GETTING AHEAD OF HERSELF

Back after a self-imposed two-month hiatus, defending US and Australian champion Osaka has not missed a beat and was too good for Viktorija Golubic in a 6-3 6-2 victory.

Osaka won 24 of 26 service points in the first set and 37 of 45 in the second, facing break point only once in a one-sided affair.

"It would mean a lot to win gold here, but I know it's a process," she said. "I know these are the best players in the world and honestly I haven't played in a while, so I'm trying to take it one notch at a time.

"All in all, I'm just really happy to be here. I haven't been in Tokyo for a couple of years."

Svitolina was not as comfortable with the fourth seed rebounding from losing the opening set to defeat Ajla Tomljanovic 4-6 6-3 6-4. Maria Sakkari (14) awaits in the next round.

Carla Suarez Navarro earned her first win since recovering from cancer in round one and battled valiantly against Karolina Pliskova (5) before eventually losing in three sets.

Garbine Muguruza (7), Barbora Krejcikova (8) and Belinda Bencic all coasted through in straight sets, as did Anastasia Pavlyuchenkova (13) and Elena Rybakina (15).

TEARS FOR IGA 

Swiatek, whose father was an Olympic rower, would have had strong designs on a deep run at the Games but was beaten 6-3 7-6 (7-4) by Paula Badosa.

The Pole was left in tears after the defeat, and was still sobbing at her chair several minutes after the end of the match.

Sabalenka also bit the dust, going down in three sets to Donna Vekic, while Petra Kvitova lost the deciding set of her tie with Alison Van Uytvanck 6-0 to bow out with a whimper.

Iga Swiatek says adjusting to the tricky Tokyo conditions will be key to winning gold after she came through her Olympics opener on Saturday.

The Polish athlete was the highest-ranked seed in action in the women's singles in the Japanese capital and comfortably dispatched of Mona Barthel 6-2 6-2.

World number one Ash Barty gets her individual campaign underway on Sunday but the Wimbledon champion was a doubles victor on the first day of action on the tennis courts.

SWIATEK OUT TO ADJUST

Swiatek was on court for a little over an hour, breaking serve six times and firing down 13 winners to Barthel's eight.

The tough hot and humid conditions were a big talking point at Ariake Tennis Centre on Saturday, and Swiatek – whose father represented Poland as a rower at the 1988 Olympics – had her say.

"I'm pretty happy that I'm into the second round and for sure not only the temperature was hard, but also the sun because on one side it was pretty hard to serve," she said. 

"But we had to adjust quickly and change our toss, so that was hard, but you know I would say the players who can adjust quicker are going to be the best ones here."

KREJCIKOVA BENEFITS FROM DIYAS RETIREMENT

Eighth seed Barbora Krejcikova was 5-2 up against Zarina Diyas before her opponent had to withdraw with an ankle problem.

The Czech now meets Leylah Annie Fernandez in the second round. Fellow seeds Belinda Bencic (9), Anastasia Pavlyuchenkova (13), Maria Sakkari (14) and Elena Rybakina (15) all made it through round one.

But Kiki Bertens, the 16th seed, was sent packing 6-4 3-6 6-4 by Marketa Vondrousova.

BARTY REVELS IN TEAMING UP WITH CHILDHOOD FRIEND

Barty is fresh off her triumph at SW19 earlier this month, and the amiable Aussie started her Olympics adventure alongside long-time friend Storm Sanders.

The sixth feeds hammered home pair Nao Hibino and Makoto Ninomiya 6-1 6-2.

"Playing with my childhood friend in what is a dream for both of us is really cool. And to be here in some of the most unique circumstances I think ever for an Olympic Games, it's really awesome for us," Barty said.

"We're very grateful and thankful that we're able to be here to play and to experience what is really cool Games."

Nina Christen of Switzerland finished 16th in the 10-metre air rifle at the Rio Olympics, but she became a footnote to history five years later as the first athlete to secure a medal at Tokyo 2020.

The 27-year-old locked up the bronze medal several minutes before China's Yang Qian beat Anastasiia Galashina of the Russian Olympic Committee to take gold in the first medal event of the Games.

As soon as she was eliminated from contention for the final two, Christen flashed a smile and waved, knowing she had at least won a spot on the podium this time – no small feat on this stage.

After the first medal ceremony of the Tokyo Games, she spoke about the pressure as the competition entered the final rounds.

"You just try to not reach your head out for the medal before you have the medal," Christen said. "That is the worst thing you could do. Having in your mind, 'Oh I could win a medal, or I could be eighth which would be a failure'.

"So you just try not to think about both of them, you just try and think about what your job is like breathing, holding, aiming, balance, triggering, and then follow through.

"It helps to not think about what is behind you and obviously there are a lot of cameras and a lot of people. And it would be even more if COVID would not have hit. So yeah that is the thing you have to do, otherwise you would just crack."

Sixth seed Swiatek rolls in tennis opener

Two seeded players enjoyed easy victories in the women's singles draw as play began at the Ariake Tennis Park.

Sixth-seeded Iga Swiatek of Poland, the 2020 French Open champion, cruised past Germany's Mona Barthel 6-2 6-2 to open her first Olympics.

Anastasia Pavlyuchenkova, the 11th seed representing the Russian Olympic Committee, had an even easier time in a 6-0 6-1 rout of Italy's Sara Errani.

Pavlyuchenkova will face Germany's Anna-Lena Friedsam, who upset Great Britain's Heather Watson 7-6 6-3 in another early match.

In doubles, there was an eye-catching result for Britain's Andy Murray and Joe Salisbury, who took out French second seeds Pierre-Hugues Herbert and Nicolas Mahut, scoring a 6-3 6-2 victory.

Men's gymnastics gets under way

Nikita Nagornyy turned in the strongest showing in the opening group as men's gymnastics got under way.

Nagornyy, who won the all-around at the 2019 World Championships and was part of Russia's silver medal-winning team at Rio 2016, posted an 87.897 to lead subdivision one, which included gymnasts from the Russian Olympic Committee (ROC), China, Ukraine and Spain along with individuals from other nations.

But his showing was not enough to put the Russians on top, as China earned the top score in the group with a 262.061 to the ROC's 261.945. The top eight ranked teams qualify for the team final, with two subdivisions still to compete Saturday.

"I don't think our team was really good today, but we made our best effort," Nagronyy said. "We have a lot to do."

Brazilians start strongly on the beach

Brazil's two returning beach volleyball medallists are off to a strong start five years later.

Alison Cerutti won gold in Rio and is teamed with new partner Alvaro Morais Filho for Tokyo. They won their opening match 2-0 against Argentina's Nicolas Capogrosso and Julian Amado Azaad.

On the women's side, Rio silver medallist Agatha Bednarczuk, also with a new partner in Eduarda Santos Lisboa, won by the same score against Ana Gallay and Fernanda Pereyra of Argentina.

While she was happy to advance, Agatha found the difference between Rio's raucous crowds and Tokyo's COVID-driven quiet jarring.

"It's so different. In Brazil we have the biggest support there. Many, many people cheering for us, and here, it's silence," she said.

"Here we need to put our emotion (aside) because we don't receive the emotion from the people. For me, this is very important because I like to play with emotions."