Teenager Dominic Stephan Stricker produced the shock of the day at the Stuttgart Open as he knocked out second seed Hubert Hurkacz in the round of 16.

The 18-year-old wildcard, ranked 335 in the world, claimed a straight sets victory courtesy of tie-breaks, as had been the case in his previous outing against Radu Albot.

And his reward for a 7-6 (7-5) 7-6 (7-5) win over a man placed 315 places higher than him in the men's rankings is a quarter-final tie against Sam Querrey.

The American sealed his passage into the last eight by beating qualifier James Duckworth 6-4 7-6 (9-7) on Thursday.

Top seed Denis Shapovalov's place in the next round remains in doubt going into Friday after the Canadians clash with Feliciano Lopez was cut short by rain with both men having taken a set.

The winner of that final set will face former world number three Marin Cilic, who comfortably beat Nikoloz Basilashvili 6-3 6-2.

Another Canadian also remains in the draw in the form of third-seeded Felix Auger-Aliassime after his 6-3 7-6 (7-4) win over Lloyd Harris.

There, he will face sixth seed Ugo Humbert after his straight sets win over wildcard entry Yannick Hanfmann.

The quarter-final line-up is completed by fourth seed Alex de Minaur, who beat compatriot Jordan Thompson, and Jurij Rodionov, whose progress was aided by Peter Gojowczyk's first-set retirement.

Rising star Casper Ruud continued his impressive 2021 with a straight-sets win over Denis Shapovalov in the Geneva Open final to win his second career title.

The world number 21 prevailed 7-6 (8-6) 6-4 in the first top-level meeting between the two players to add to the Argentina Open crown won – also on clay – in February 2020.

Ruud did not face a single break point in the match, which lasted an hour and 40 minutes, and needed only one break conversion himself to see off second seed Shapovalov.

"It's tough to find all the words," said Ruud, who has a 15-4 record on clay this year. 

"It was such an amazing week here in Geneva. I was always looking forward to coming to this tournament.

"I watched it on TV for many years when I was younger and it always seemed like a nice place, so I guess I know why I wanted to come here.

"It's been going well and this week has been unbelievable for me."

Looking to lay down a marker ahead of the upcoming French Open, where he reached the third round last year, third seed Ruud took little time to get going against Shapovalov.

However, the first set went the way of the serve to set up a tie-break, which the Norwegian eventually took with his fifth set point after Shapovalov won four points in a row.

Shapovalov was competing in his third tour-level final after winning the Stockholm Open and losing in the Paris Masters final in 2019, but he struggled to break his opponent.

Ruud earned a break in the fifth game of the second set and saw the job through to keep his momentum going ahead of the second grand slam of the year.

Asked about his aims for Roland Garros, Ruud said: "Well, it's the toughest clay court tournament of the year.

"This season I am playing well on the clay and I'm looking forward to Paris. I hope I can make the second week, that's all I can say.

"If I'm in the second week I will be very happy of course."

Stefanos Tsitsipas insists it must be purely business when he tackles Italian teenager and fellow tennis artisan Lorenzo Musetti in the Lyon Open semi-finals.

Ahead of a tilt at the French Open, for which he is among the favourites, world number five Tsitsipas has been tuning up his game at this week's ATP 250 tournament.

The Greek star was sharp in posting a 6-3 6-4 win over Japan's Yoshihito Nishioka, and 19-year-old Italian Musetti awaits him on Saturday.

Tsitsipas dropped just four games when he crushed Musetti in an Acapulco semi-final in March, but he senses more of a threat this time from the exciting youngster.

"We played in different conditions. Acapulco was a hardcourt match and with altitude," said Tsitsipas, speaking on Amazon Prime. "The conditions here are different. He's someone who enjoys playing on clay.

"We share a similar game style I think with a one-handed backhand, which is beautiful to see, but tomorrow it's going to be serious business I knew he can play good on this surface. I know he can elevate his game, so it's important for me to be in the semi-finals."

Musetti overcame Slovenian Aljaz Bedene 6-3 7-6 (7-2) in their quarter-final, scrambling through a chaotic second set in which he trailed 5-2 at one stage but then reeled off four straight games, only to fail to serve out.

Thankfully for the youngster, he pulled through the tie-break.

"It was a crazy end," said Musetti. "I was 6-5 up, and at 30-30 played a really bad volley and hit an underarm serve. Sometimes I go out of my mind. I am really proud of myself as I was 2-5 down in the second set and I stayed focused. I tried to play each point at my best."

Russian Karen Khachanov marked his 25th birthday with a 6-1 7-6 (7-3) win over Frenchman Richard Gasquet, veteran doyen of the single-handed backhand.

Khachanov faced a wait to learn who he must face in the semi-finals, however, with Cameron Norrie and Arthur Rinderknech level at one set all overnight, after rain forced an early end to play.

At the Geneva Open, Norway's Casper Ruud will tackle Canadian Denis Shapovalov in Saturday's final.

Ruud saw off Spaniard Pablo Andujar 6-3 6-2, while Shapovalov earned a 6-4 7-5 win against Uruguayan qualifier Pablo Cuevas.

Denis Shapovalov relished feeling much better on court as he impressively bounced back from two consecutive defeats to win at the Madrid Open.

The number 11 seed brushed aside the challenge of Dusan Lajovic on Sunday, winning 6-1 6-3 in the first round.

Shapovalov had suffered disappointment on Thursday when he was knocked out in the second round of the Estoril Open, an event where he was the number one seed.

He has not reached the quarter-finals in his previous two ATP Tour events but won 90 per cent of his first-serve points against Lajovic, hitting 21 winners to his opponent's five.

"Just definitely felt a lot better - I felt very good on the court," Shapovalov said after a 63-minute win in which he did not lose serve. 

"I'm just happy to get the first win.

"Not much can change in the span of a couple of days, but Madrid is a place where I have had a lot of success, from back in juniors to making semis here in the Masters [1000 event] and finals of Davis Cup.

"It's just a place where it kind of feels like home to me and I just feel so comfortable." 

Shapovalov will face Alexander Bublik – who saw off Marton Fucsovics in straight sets – in round two.

Tommy Paul, meanwhile, will play Andrey Rublev after defeating Pedro Martinez.

In the only match of the day to go the distance, Australian Alex de Minaur battled back to triumph 4-6 7-5 6-1 against Jaume Munar.

He will play either Lloyd Harris or Grigor Dimitrov, who are scheduled to do battle on Monday.

Stefanos Tsitsipas battled through to the Miami Open round of 16 and he was joined by Andrey Rublev on Monday.

Greek star and second seed Tsitsipas got the better of 2014 US Open runner-up Kei Nishikori in Miami.

Rublev continued his fine 2021 with a straight-sets demolition of Marton Fucsovics at the ATP 1000 tournament.

In-form Aslan Karatsev, however, bowed out following a surprise loss to Sebastian Korda.

TSITSIPAS HALTS NISHIKORI

Despite a mid-match wobble, Tsitsipas overcame Nishikori 6-3 3-6 6-1 to reach the fourth round.

Former world number four Nishikori forced a deciding set but Tsitsipas withstood the Japanese's comeback.

Tsitsipas, who hit 32 winners, will meet Lorenzo Sonego for a place in the quarter-finals after the 24th seed defeated Daniel Elahi Galan 7-6 (8-6) 6-3.

RUBLEV STAYS HOT

Russian fourth seed Rublev made light work of Fucsovics 6-2 6-1 in just 52 minutes.

Rublev leads the ATP Tour with 18 victories this season after eliminating the in-form Hungarian, ahead of top seed Daniil Medvedev (16-2).

The result secured a third win for Rublev over 29th seed Fucsovics this month.

"I was laughing, because of [the] situation and plus Marton also told me, 'I don't want to see you. I don't want to see you'," Rublev said, cracking a laugh. "[It was] just a situation that [was] fun, and I feel sorry."

Awaiting Rublev is 2014 US Open champion and former world number three Marin Cilic, who beat Lorenzo Musetti 6-3 6-4.

KARATSEV CONQUERED

For only the third time this year, Australian Open semi-finalist and Dubai Tennis Championships winner Karatsev tasted defeat following a 6-3 6-0 loss at the hands of Korda.

American sensation Korda became the first player outside the top five to beat Karatsev this year, with the latter's previous two losses coming against world number one Novak Djokovic and world number four Dominic Thiem.

"It is super special [to reach the Round of 16], especially playing a guy who was as hot as he was," said Korda. "I just took the tactics that I used [against him] at Roland Garros and it worked out really well today."

Diego Schwartzman stands in the way of Korda and the quarters after the fifth seed accounted for Adrian Mannarino 6-1 6-4.

Elsewhere, Denis Shapovalov – the sixth seed – was upstaged by Hubert Hurkacz 6-3 7-6 (8-6).

Another Canadian awaits Hurkacz after 12th seed Milos Raonic was a 6-4 7-5 winner against Ugo Humbert.

Stefanos Tsitsipas continued his strong run of form en route to the Miami Open third round, while Aslan Karatsev's maintained his fairytale run in 2021.

Greek star Tsitsipas flexed his muscles in a straight-sets win over Damir Dzumhur on Saturday.

Australian Open semi-finalist and Dubai Tennis Championships winner Karatsev enjoyed a victorious Miami debut.

Andrey Rublev, Diego Schwartzman, Denis Shapovalov, Marin Cilic and Milos Raonic also progressed at the ATP 1000 tournament.

TSITSIPAS STAYS HOT

World number five Tsitsipas eased past Dzumhur 6-1 6-4 in his first appearance since losing in last week's Mexican Open final.

Tsitsipas (15-4) became the third player to reach 15 wins this season, the second seed following in the footsteps of Russian duo Rublev (17-3) and Daniil Medvedev (15-2).

"It was a great match, especially against a guy that I probably don't have a good record playing against in the past," said Tsitsipas. "I started the match very strong, breaking him twice and taking a big lead in the score, and I think the things worked out by themselves after that."

Tsitsipas will face Kei Nishikori after the Japanese outlasted Aljaz Bedene 7-6 (8-6) 5-7 6-4.

NO STOPPING KARATSEV

Karatsev's Miami Open debut ended in a 6-4 6-3 win for the 17th-seeded Russian over Mikhail Kukushkin.

Already in the ATP's top 100 and set to keep climbing, Karatsev broke serve four times en route to the next round, where Sebastian Korda awaits after upstaging 10th seed Fabio Fognini 1-6 6-4 6-2.

"Of course it gives me confidence to win my first title, but you arrive here and it’s a different surface and new tournament," said Karatsev, who ended last season ranked 112th before bursting into the top 30 behind his semi-final run at Melbourne Park. "So you try [to think of it] as a new tournament and new place, but of course it gives me a lot of confidence."

Karatsev owns a 13-2 record this year, with his only two losses coming against world number one Novak Djokovic and US Open champion Dominic Thiem.

RUBLEV ROLLS ON

Fourth seed Rublev has proven to be remarkably consistent, highlighted by his crushing 6-1 6-2 rain-interrupted victory against Tennys Sandgren.

Having equalled his previous best run in Miami, Rublev will play 29th seed Marton Fucsovics who took down Thanasi Kokkinakis 7-6 (7-3) 6-7 (4-7) 6-4.

Rublev has won a Tour-leading 17 matches this year.

Elsewhere, fifth seed Schwartzman was a 6-3 6-3 winner against Yasutaka Uchiyama, Shapovalov – the sixth seed – trumped Ilya Ivashka 6-7 (5-7) 6-4 6-4 in a marathon, 12th seed Raonic accounted for Jordan Thompson 6-2 6-1, former US Open winner Cilic surprised 13th seed Christian Garin 3-6 7-5 7-6 (7-5), while 15th seed Alex de Minaur was eliminated.

Andrey Rublev's ATP 500 winning streak came to an end at the hands of Aslan Karatsev on a history-making day at the Dubai Tennis Championships.

Rublev had won 23 consecutive matches at this level, second only to Roger Federer (28), but Karatsev finally ended the Russian's remarkable run to progress to his first ATP singles final.

Karatsev, who incredibly went from qualifying to the semi-finals of the Australian Open this year, defeated his compatriot 6-2 4-6 6-4.

He became the first Wild Card to reach the final since Thomas Muster in 1997, doing so by hitting 41 winners and forcing 16 break points – of which he won four – during two hours and 12 minutes on court.

"It was a really tight match [against a] tough opponent," Karatsev said in his on-court interview.

"It was an unbelievable performance [from Andrey]. He didn't lose a match at an ATP 500 in [one year]. Everything was decided in one or two points, I feel happy."

The championship match will be between two first-time Dubai finalists after Lloyd Harris stunned Denis Shapovalov in the other semi-final.

World number 81 Harris, who overcame top seed Dominic Thiem, 14th seed Filip Krajinovic and former US Open finalist Kei Nishikori to reach the last four, came from a set and 4-2 down to defeat world number 12 Shapovalov.

He prevailed 6-7 (5-7) 6-4 7-6 (8-6) to reach a maiden ATP 500 final and become the first qualifier to reach the showpiece in Dubai.

"I don't have many words right now. I am super happy with that win," Harris said on court afterwards.

"Being a set and 2-4 down is mentally and physically a little bit troublesome for me, but I found my best tennis from there. I am just extremely happy with the result right now."

Denis Shapovalov secured a straight-sets win over Jeremy Chardy to set up a semi-final showdown with qualifier Lloyd Harris at the Dubai Tennis Championships. 

The third seed struck 26 winners en route to a 7-5 6-4 triumph on Thursday, but it was his serve that pleased him most.

Shapovalov, ranked 12th in the world, sent down 10 aces as Frenchman Chardy was deprived of any break-point openings.

"I've focused on my serve a lot in the past couple of weeks," the Canadian said.

"I have worked on placing it and tried out different types of serves to have more variation. I hope I can continue that.

"I've also worked on my footwork and positioning during rallies. I am feeling the ball well on both sides. If I am moving well, everything goes into place."

Harris was a surprise winner over Kei Nishikori, sealing a 6-1 3-6 6-3 success to dump out the former world number four.

Second seed Andrey Rublev defeated Marton Fucsovics 7-5 6-2 and will now face fellow Russian Aslan Karatsev.

Wildcard Karatsev continued his run with a hard-fought victory over teenager Jannik Sinner, coming from a set down in a 6-7 (5-7) 6-3 6-2 win.

Novak Djokovic admitted there was plenty of room for improvement after coming through a "difficult spot" at the Australian Open, where Nick Kyrgios thrilled the crowd with an impressive comeback.

Top seed Djokovic was made to work for his 6-3 6-7 (7-3) 7-6 (7-2) 6-3 triumph against Frances Tiafoe as he reached the third round in Melbourne. 

Kyrgios is also through, albeit he even surprised himself by rallying from the brink of defeat to knock out 29th seed Ugo Humbert in the evening session. 

Stan Wawrinka was on the wrong of an upset on Wednesday, but there were no such problems for fellow seeds Dominic Thiem, Alexander Zverev, Diego Schwartzman and Milos Raonic. 

Meanwhile, Denis Shapovalov and Felix Auger-Aliassime will have to put their friendship to one side when they face each other next, the former setting up the all-Canadian clash by beating Bernard Tomic in three sets.

'PASSIVE' DJOKOVIC STILL MAKING PROGRESS

In the first meeting between the pair, the impressive Tiafoe went toe-to-toe with Djokovic on Rod Laver Arena.  

The 23-year-old American's performance – coupled with the Melbourne heat – made the eight-time Australian Open champion sweat, albeit Djokovic felt he could have made life easier for himself.

"I was at times not feeling my timing as well as I normally am. Credit to him. I think he has managed to come out with a great performance and quality of tennis. He put me in a difficult spot," he said. 

"I had my chances early in the second set. If I broke him there, maybe the course of the match would be different.   

"But again, he was holding his serve very well. I was not really using my break-point chances very well. At times I was too passive. Just wasn't feeling the ball today as well as I normally do." 

Next up for Djokovic is another player from the United States in the form of Taylor Fritz, who ousted compatriot Reilly Opelka in a five-set battle.

IN THE NICK OF TIME

Kyrgios described his clash with Humbert as "one of the craziest matches I've ever played" after prevailing 5-7 6-4 3-6 7-6 (7-2) 6-4 - much to the delight of an enthralled audience who watched the drama unfold on John Cain Arena.

The Australian smashed a racket, lost his cool with umpire Marijana Veljovic over a faulty net cord sensor and had to save a pair of match points before eventually coming out on top in a see-saw battle.

"I just remember, down that end, when I was a couple of match points down, I don't know what was going on," Kyrgios - who dropped to his knees after sealing victory - said in his on-court interview.

"If you were inside my head, there were some dark thoughts in there. But I live to fight another day and hopefully I can continue to play good tennis in front of you guys."

His reward is a clash with Thiem, the third seed having dismissed the challenge of German Dominik Koepfer in straight sets as he dropped just six games.

STAN-D AND DELIVER

Wawrinka appeared on course to survive a serious scare when he rallied from two sets down against Marton Fucsovics, but the Swiss was unable to seize on the chances that came his way in a tense tie-break. 

Fucsovics had needed over four hours to overcome wild card Marc Polmans in the previous round and, once again, found a way to get over the finishing line at the end of a Melbourne marathon. 

The Hungarian trailed 6-1 during the decisive breaker, yet hit back to stun the 17th seed 7-5 6-1 4-6 2-6 7-6 (11-9). For Wawrinka, there was frustration at the missed opportunities, albeit he also praised his conqueror. 
  
"From 6-1 up, I started to hesitate a little bit in the way I was playing," he said. "I wanted to put the ball maybe too much in and I [was] not going completely for my shots and that's when I started to miss a little bit and it helped him to come back in the match.  

"He was fighting well, he's a tough player, he's a good player and he deserved to win."