Rafael Nadal has denied he has already decided to follow Roger Federer into retirement after this year's French Open.

The Spaniard wil turn 37 in June, and calling time on his career at the grand slam he has won a record 14 times might be the ideal way to sign off.

Making predictions for the season, Germany's Alexander Zverev told Eurosport: "Unfortunately, I think Rafa will retire at Roland Garros. I don't want it to happen, but I think he will have a great tournament, potentially win it and say goodbye."

That would mean Nadal joining his former great rival Federer in waving goodbye to a glorious career after the Swiss played for the last time at the Laver Cup in September. Nadal's tears that night in London pointed to a realisation his own time on tour was also nearing its end.

However, Nadal denies Zverev has been given any encouragement to throw out such a specific retirement suggestion, which was revealed ahead of the Australian Open.

Nadal is the defending champion in Melbourne, and he also took the Paris slam last year to reach 22 for his career, putting him one ahead of Novak Djokovic.

"I don't know what's going to happen in six months," Nadal said, quoted by Eurosport.

"I have a very good relationship with Zverev, but not enough to confess something like that to him.

"The reality is that I'm here to play tennis, try to have a great 2023, fight for everything that I have struggled throughout my career, and I don't think about my retirement.

“You think about it week after week because that's how you show me at every press conference. But I will answer the same every time you ask me."

Nadal has lost six of his last seven tour-level matches, suggesting he might struggle to make serious inroads in his title defence, which starts against Britain's Jack Draper on Monday.

Asked if he felt vulnerable, Nadal said: "Yeah, of course. Without a doubt. I have been losing more than usual, so that's part of the business.

"I think I am humble enough to accept that situation and just work with what I have today. I need to build again all this momentum. I need to build again this confidence with myself with victories. But it's true that I have been losing more than usual.

"I already have been here for three weeks, practising every day with the conditions, with the best players. That helps a lot in general terms.

"My situation, I don't know what can happen on Monday, but my personal feeling, without a doubt, is better now than three weeks ago, in general terms."

Iga Swiatek starts the Australian Open as almost as strong a favourite to win the women's singles as Novak Djokovic is for the men's event.

Considering Djokovic is a nine-time champion in Melbourne, and Swiatek has never reached the final, that is some going and indicative of the Polish player's dominance on the WTA Tour over the last 11 months.

Swiatek ended last year with eight titles to her name, winning the French Open and US Open among them, and the 21-year-old has accrued more than twice as many ranking points as the next player on the WTA list, Ons Jabeur.

Her ascent to become the dominant woman in tennis has been remarkable, and Swiatek has also earned admiration for her efforts to raise funds for children in war-hit Ukraine.

But is she such an outstanding favourite for the Melbourne Park title as the odds-makers have it?

Since the US Open, she has been a champion at just one – modest by her standards – of the four tournaments she has contested, including the United Cup team event.

Here, Stats Perform looks at five others who might have a say in the destination of the year's first major.

Jessica Pegula

Swiatek was reduced to tears after a 6-2 6-2 drubbing by Pegula on January 6 at the United Cup, her first loss of the year.

She later described Pegula's performance as "the perfect match", and will hope the American cannot always rise to that level.

"It's always hard when you lose, especially when you're playing for the team and your country," Swiatek said at the time, explaining her post-match tears.

Swiatek had won all four of the matches they contested in 2022, dropping only one set, with quarter-final wins on the way to her two grand slam triumphs included in that set.

The result in Sydney, therefore, might have been just a blip, but Pegula is number three in the world for a reason, and Swiatek will surely want to avoid her over the coming fortnight.

Coco Gauff

Is now Gauff's time? There's a question that has been buzzing around the tennis circuit for at least a couple of seasons, despite the American being just 18 years old.

Time, it should be clear, is firmly on her side. She soared to fourth in the rankings in October but has slipped a little since, while remaining firmly established in the top 10.

Given her great talent, Gauff should be resident in the top 10 for many years to come, so we can afford to wait before watching her fly. The sometimes-erratic forehand remains in need of fine-tuning, and Gauff began this year with just two career singles titles to her name after missing out on a trophy in the 2022 season.

However, she reached a first grand slam final last June, losing to Swiatek in Paris, and began 2023 by capturing a title in Auckland where, as top seed, she made light work of the field.

The victory made her the sixth American player to secure three or more WTA-level titles before turning 19 in the last 40 years, after slam winners Monica Seles, Jennifer Capriati, Lindsay Davenport, Venus and Serena Williams.

That is some company for Gauff, who will face Katerina Siniakova in the first rout in Melbourne, to be keeping, and her time will come. It might even come in Melbourne.

Ons Jabeur

After finishing runner-up to Elena Rybakina at Wimbledon and Swiatek at the US Open, Jabeur is targeting a third successive slam final.

The Tunisian would win most popularity contests on the Tour, but she wants one of the big trophies now, and has to be seen as a strong contender in Australia.

Her preparations took a knock with a loss to 18-year-old Czech Linda Noskova at Adelaide International 1, but that will only have made Jabeur work harder in the build-up to the major.

She was gutted to have to pull out of the Australian Open with a back injury last year, and a first-round loss at the French Open followed, but Jabeur came good at the next two majors, albeit falling at the final hurdle.

Aryna Sabalenka

At this time last year, Sabalenka was in crisis, her serve a massive weakness as she struggled to deliver the ball safely.

She recovered from going a set down in three consecutive matches at the Australian Open before losing a rollicking tussle in round four with Estonian veteran and upset specialist Kaia Kanepi.

Sabalenka served a wretched 15 double faults in that match, which was sadly more or less par for her in the early stages of the 2022 season, but the Belarusian got her act together, overcome those yips, and finished the year strongly.

A semi-final run at the US Open was followed by an appearance in the WTA Finals title match, where she lost a close encounter with Caroline Garcia.

Sabalenka began this year not with the serving jitters, but with the Adelaide International 1 title, not dropping a set all week.

She has a big game and with it growing confidence. At the age of 24, she should be entering her prime years, and 2023 could be a special 12 months for the woman with the tiger tattoo.

Zheng Qinwen

The WTA's 2022 Newcomer of the Year winner, Zheng is a 20-year-old Chinese player who could soon follow in the footsteps of compatriot Li Na and begin scooping the biggest prizes in tennis.

How soon? Well, probably not quite yet, but then again very few picked out the then 54th-ranked Swiatek to win the 2020 French Open, the moment that launched her to stardom.

Zheng has rocketed to 30th in the rankings, having begun last year at 126th on the WTA list, and should be considered capable of halving her ranking over this season.

She first came to major prominence at the French Open, when she defeated Simona Halep and for a while also had Swiatek's number in their fourth-round match, winning the first set before menstrual cramps and a leg problem caused her to lose momentum.

The WTA Tour is a learning curve and slam-level success might not come immediately for Zheng, but that newcomer award came her way because she is a player shaping up to have a big say in the sport's future. Along with the likes of Gauff and Swiatek, she could still be a big factor in a decade's time.

Nick Kyrgios insists he is serious about being ready to quit tennis the minute he wins a singles grand slam title.

The Australian went close last year to ending his long wait, only to lose in four sets against Novak Djokovic in the Wimbledon final.

Now aged 27, Kyrgios wants to achieve glory at a major to satisfy that urge, before stepping off the court for good. If it comes at the Australian Open over the coming fortnight, it will be all the better for him.

Asked whether he stood by his previous comments, Kyrgios said: "A hundred per cent. It's a lot of training, a lot of work, and I just want to be able to eat whatever I want, drink what I want to drink and just relax.

"It's a hard lifestyle, the dedication these guys show day in day out. I did a bit of that last year, had a great year to show the world I'm still one of the best.

"I'm going to try to do it this year, and hopefully I can do it, but it'll be hard."

Kyrgios is ranked 21st by the ATP, but that can be considered a false position, given he collected no points for his career-best Wimbledon run. The tours stripped the London slam of ranking points due to its banning of players from Russia and Belarus.

The 1,200 points Kyrgios would ordinarily have taken away from the All England Club would have nudged him towards a top-10 placing.

There is the tantalising prospect of Kyrgios facing nine-time Melbourne Park champion Novak Djokovic in the Australian Open quarter-finals this year, and they went through a light-hearted dress rehearsal on Rod Laver Arena on Friday.

Speaking after that exhibition match, Djokovic said Kyrgios' two wins from their previous three tour-level encounters meant the sky was the limit for the man from Canberra.

"He is 2-1 against me, so as far as I'm concerned he can win anything," said Djokovic.

According to Djokovic, Kyrgios had been unaware of the potential for a meeting between the pair in the Australian Open last eight.

Serbian Djokovic has done his homework though, and appears to have mapped out his potential route to what would be a record-equalling 22nd men's singles grand slam title.

"I have to be honest, I think most of the guys are studying the draw pretty seriously, but you have to take it one match at a time," Djokovic said, speaking on Channel Nine.

"We think every player has so much motivation and inspiration to be able to play his best in the court, to perform well, so you cannot underestimate anybody, you cannot take any match for granted.

"It's a hopefully long two weeks. I know Nick and I are in the same part of the draw – he didn't know that by the way. Before the match I told him."

Novak Djokovic returned to action in front of a packed Rod Laver Arena crowd for the first time in two years, and declared: "It's great to be back."

The nine-time Australian Open champion was denied a role in last year's tournament when his vaccination status, having refused a COVID-19 jab, led to him being detained in a Melbourne immigration centre and later deported.

He was briefly released in January 2022 to practise at Melbourne Park before the tournament began, only to be effectively thrown out of the country days later.

With Australia's border controls having since been relaxed, and vaccination status no longer a condition of entry, Djokovic has had the red carpet rolled out this year, befitting his status as the most successful male singles player in the Australian Open's history.

He faced Nick Kyrgios in an exhibition match on Friday evening in Melbourne, with the stadium court sold out and the match screened on national television.

Kyrgios won 4-3 2-4 10-9, in what was a largely light-hearted encounter, a jumped-up practice session. It inevitably lacked the intensity of their last meeting, when Djokovic prevailed in four sets in the 2022 Wimbledon final.

A fierce backhand from Kyrgios in the match tie-break briefly caught out Djokovic, who was wrong-footed and volleyed out of court before slumping to the floor as though shot.

There was more than a little dramatic licence about his fall, and about the match in general, typified by the pair being joined on court by wheelchair players and a pair of leading juniors for the decisive tie-break.

The result did not matter, though it will if these two meet in the quarter-finals of the year's opening grand slam, as they might after the draw was revealed on Thursday.

Djokovic, who did not appear hampered by a recent hamstring niggle, told the crowd: "It just feels great to be back in Australia, back in Melbourne.

"This is the court and the stadium where I created the best memories of my tennis career. Back in 2008 it was the first time I won a grand slam here, and 15 years later I'm here again, and I'm competing at a high level, so I must be grateful for this opportunity to be here.

"Thank you guys for welcoming me in a good way tonight, I appreciate it."

It was a night for jollity and camaraderie, but should both reach that quarter-final date, Djokovic said: "I don't think we'll be this friendly to each other."

Kyrgios, who defended Djokovic during last year's January crisis, said of the 35-year-old Serbian: "It's so important to have him around.

"One of the greatest already left us last year, Roger [Federer], and I don't think we actually knew how special the guys are to our sport, so every time Novak's around at these events I want to beat him, even though I can't at a grand slam."

The Australian Open begins on Monday, when Djokovic facing Spain's Roberto Carballes Baena first. Djokovic is chasing a 22nd grand slam title, which would equal the men's singles record held by Rafael Nadal.

Kyrgios, yet to win a singles slam, starts against Russian Roman Safiullin.

Iga Swiatek has no interest in what people expect from her and the world number one will not be "living in the past" as she targets more success this season.

Swiatek was in a class of her own last year, winning a staggering eight titles to firmly establish herself as the best player in the world.

A second French Open title and a maiden US Open triumph were the highlights for the 21-year-old in a stellar 2022.

The Pole will start her quest to win the Australian Open with a first-round match against Germany's Jule Niemeier at Rod Laver Arena on Monday.

Swiatek is the favourite to be crowned champion at Melbourne Park, but will not be putting too much pressure on herself.

"When I don't care about what people think and what their expectations of me are, it's easier for me to succeed," Swiatek told BBC Sport.

"That was what I tried my best to do in 2022.

"Although I'm proud of them, I'm not going to try to match my previous achievements because it would not be constructive.

"A season like that is something amazing and rare. Sure, I would love to do it again, but it's not advantageous to live in the past."

Swiatek was beaten by Danielle Collins at the semi-final stage of the Australian Open 12 months ago.

Nick Kyrgios believes only "a clown" would give Novak Djokovic a hard time at the Australian Open as the Serbian chases a major slice of tennis history.

It was Kyrgios who prominently came to Djokovic's defence when the nine-time champion at Melbourne Park was detained in an immigration facility and then deported ahead of last year's Australian Open due to his COVID-19 vaccination status.

The previously testy relationship between the pair has become increasingly friendly, to the point they will meet in a practice match at Rod Laver Arena on Friday, ahead of the season's first grand slam. That match sold out in a flash, reflecting the popularity of both men.

Kyrgios described their growing closeness as a "bromance" at Wimbledon last year, although Djokovic laughed off that label.

Djokovic, who has refused to be vaccinated against the coronavirus, will have many on his side over the coming fortnight as he chases a 10th grand slam in Australia and a 22nd overall, which would match Rafael Nadal's men's singles record.

Tournament director Craig Tiley has said anyone that boos Djokovic would risk being thrown out, while Kyrgios called for "respect" to be shown to the 35-year-old superstar.

Kyrgios described Djokovic as "the best that we've got", adding: "I would say, Novak's here and he hasn't made any rules. He's abided by them for the last two years or whatever.

"He's here and all he wants to do is put on a show. He's chasing things that athletes rarely are able to chase. He's one of the greatest athletes of all time, not just in the tennis court.

"I think as fans we should be appreciating that. I know there's going to be fans who are not wanting him to win, but I think they can't cross that line as fans.

"You guys have paid money to watch a guy play, it's a bit contradictory if you're going to go there and be a clown about it.

"You've got to respect him a little bit at the end of the day because he's one of the best who's ever done it."

Kyrgios has a 2-1 record against Djokovic, though both of his wins came back in 2017 and Djokovic won in four sets in their last meeting: the 2022 Wimbledon final.

Should they both win through the early rounds in the season's first grand slam, the draw is such that they could go head to head again in the quarter-finals.

Already, Kyrgios is talking about possibly abandoning doubles duty with Thanasi Kokkinakis in order to focus on singles.

He and Kokkinakis took the doubles title last year, but Kyrgios said on Thursday: "We're singles players at heart and the doubles grand slam last year was a flash in the pan.

"We haven't had one conversation about doubles yet. If we play, we play; if we don't, we don't."

Nine-time champion Novak Djokovic will make his return to the Australian Open against Spain's world number 75 Roberto Carballes Baena.

After being deported from Australia last year amid a row over his refusal of a COVID-19 vaccination, Djokovic is firmly back in favour and chasing history in Melbourne, with a record-equalling 22nd men's singles grand slam in his sights.

He begins against an opponent who in four previous main draw appearances has only ever won one singles match at Melbourne Park.

Defending champion Rafael Nadal, whose 22 slam titles Djokovic is seeking to match, has a tricky opener against rising British star Jack Draper, the world number 40.

Second seed Casper Ruud will tackle Czech Tomas Machac first up, with the 115th-ranked player unlikely to prove too daunting an obstacle for last season's French Open and US Open runner-up.

Fifth seed Andrey Rublev could face an awkward assignment against wildcard and former US Open winner Dominic Thiem, while Australia's Nick Kyrgios begins against Russian Roman Safiullin.

Neither 13th seed Matteo Berrettini nor five-time runner-up Andy Murray would have been delighted to be paired together, but that is what happened in Thursday's draw.

In the women's singles, top seed Iga Swiatek starts her bid for a first Australian Open title against Germany's Jule Niemeier, who caught the eye last year on a run to the Wimbledon quarter-finals.

American seventh seed Coco Gauff starts against Czech Katerina Siniakova, while Jessica Pegula, Gauff's third-seeded compatriot who recently beat Swiatek in the United Cup, will face Belgian Jaqueline Cristian.

Gauff could face former US Open winner Emma Raducanu in the second round. Unseeded Briton Raducanu starts against Germany's Tamara Korpatsch.

Former champions Sofia Kenin and Victoria Azarenka go head to head in the first round, with American Kenin unseeded this year and Belarusian Azarenka the 24th seed.

Azarenka's compatriot Aryna Sabalenka is fancied to do well, having banished last year's serving yips, and the fifth seed starts against Czech Tereza Martincova.

Tunisian second seed Ons Jabeur, runner-up at Wimbledon and the US Open, begins her latest quest for an elusive grand slam title against Slovenian world number 88 Tamara Zidansek.

Former US Open winner Bianca Andreescu is unseeded in Australia and Czech 25th seed Marie Bouzkova drew a possible short straw by getting the Canadian in round one.

Four-time grand slam champion Naomi Osaka has announced she is pregnant and is not expecting to play tennis again until next year.

The 25-year-old has not been in action since September and withdrew from the upcoming Australian Open on Sunday, but no reason was given for her prolonged absence.

However, Osaka revealed on her personal social media accounts on Wednesday that she is expecting her first child and will take a year out.

"Can't wait to get back on the court, but here's a little life update for 2023," she wrote alongside an image of an ultrasound. 

"The past few years have been interesting to say the least, but I find that it's the most challenging times in life that may be the most fun. 

"These few months away from the sport have really given me a new love and appreciation for the game I've dedicated my life to.

"I realise that life is so short and I don't take any moments for granted, every day is a new blessing and adventure. 

"I know that I have so much to look forward to in the future, one thing I'm looking forward to is for my kid to watch one of my matches and tell someone, 'that's my mom,' haha.

"2023 will be a year that'll be full of lessons for me, and I hope I'll see you guys at the start of the next one 'cause I'll be at Aus 2024. Love you all infinitely."

The Japanese former world number one won the Australian Open in 2019 and 2021, while also winning the US Open in 2018 and 2020.

Osaka is currently ranked 42nd in the world and has been replaced by Dayana Yastremska in the main draw for the opening grand slam of the year.

"I don't think there's a perfectly correct path to take in life," Osaka added in her post. "But I always felt if you move forward with good intentions you'll find your way eventually."

Novak Djokovic cut short a practice match against Daniil Medvedev on Wednesday as a hamstring injury lingers ahead of the Australian Open.

Record nine-time Melbourne champion Djokovic is back in Australia after he was denied entry last year and subsequently deported due to his COVID-19 vaccination status.

The 21-time major winner is expected to be a contender again at the first grand slam of the 2023 season, but his preparations were hampered by an injury scare on Wednesday.

Djokovic, who won his first title of the year in Adelaide last week, was able to complete only a single set of an exhibition against Medvedev.

"It's a hamstring that I had problems with in Adelaide actually last week," he explained to Nine's Wide World of Sports. "It was against Medvedev, when I played the semi-final, and I played with him today in a practice match.

"I just felt it a bit, pulling, and I didn't want to risk anything worse. I played a set, apologised to him, and he was understanding.

"I just want to avoid any bigger scares before the Australian Open."

Having required a lengthy medical timeout against Medvedev in Adelaide, Djokovic had described the issue as "nothing too serious".

The Serbian is also scheduled to play a practice match against home hopeful Nick Kyrgios this week.

Novak Djokovic will face Nick Kyrgios in a practice match ahead of the Australian Open.

Djokovic marked his return to Australia by beating Sebastian Korda to win his 92nd Tour-level title on Sunday in Adelaide.

Kyrgios, meanwhile, did not feature in the inaugural United Cup for Australia after withdrawing due to injury.

They will now meet in a practice match at Rod Laver Arena on Friday, ahead of the season's first grand slam.

Ticket proceeds will go to the Australian Tennis Foundation.

The duo have had a turbulent relationship in the past, though last year appeared to be on better terms.

Kyrgios came to Djokovic's defence when the Serbian was denied entry to Australia and subsequently deported ahead of the 2022 Australian Open due to his COVID-19 vaccination status.

Australia's policy on non-vaccinated individuals entering the country has now changed, and Djokovic had his three-year suspension from the nation revoked, allowing him to compete in Melbourne this year.

Krygios has a 2-1 record against Djokovic, though both of his wins came back in 2017.

They last met in the final of Wimbledon last year, with Djokovic coming out on top 4-6 6-3 6-4 7-6 (7-3).

Venus Williams has withdrawn from the Australian Open due to injury and Iga Swiatek's participation could be in doubt.

The American was given a wildcard for the first grand slam of the year, but suffered an injury setback at the ASB Classic this week.

Williams was beaten by Zhu Lin of China in the second round of the tournament in Auckland on Thursday and it was revealed on Saturday she will not play at Melbourne Park.

The 42-year-old, who has shown incredible longevity in her illustrious career, is a seven-time grand slams singles champion and winner of 14 major doubles titles.

Williams won four of her grand slam doubles crowns at the Australian Open and lost her two singles finals in 2003 and 2017.

Australian Kim Birrell has been awarded Williams' wildcard place nine days before the tournament gets under way.

Meanwhile, world number one Swiatek has withdrawn from the Adelaide International 2 next week due to a shoulder injury.

Swiatek was in tears after she was beaten by Jessica Pegula while representing Poland against the United States in the United Cup on Friday.

Carlos Alcaraz has pulled out of the Australian Open after suffering a leg muscle injury in training.

The 19-year-old world number one won the US Open last September and would have been among the favourites at Melbourne Park and one of the players capable of challenging nine-time champion Novak Djokovic.

However, Alcaraz announced he would not be fit enough in time to feature, with a problem with a hamstring leaving him sidelined for the tennis season's opening grand slam.

He wrote on Instagram: "When I was at my best in preseason, I picked up an injury through a chance, unnatural movement in training.

"This time it's the semimembranosus muscle in my right leg. I'd worked so hard to get to my best level for Australia but unfortunately I won't be able to play the Care A2+ Kooyong or the Australian Open.

"It's tough, but I have to be optimistic, recover and look forward. See you in 2024 @australianopen."

The Kooyong event is an exhibition tournament ahead of the major, and it is the Australian Open where his presence will be most sorely felt.

Alcaraz has emerged as the pick of the new generation of players, with his high-intensity game winning him a legion of supporters and bringing him a host of titles already.

He earned $7.6million and picked up five singles titles last season, including the first grand slam crown of his career in New York, ending the year with a 57-13 win-loss record and the ATP top ranking.

Alcaraz's compatriot Rafael Nadal is the defending champion in Melbourne, while Djokovic returns this year after being deported from Australia 12 months ago amid a vaccination saga.

Former world number one Ash Barty has revealed she is pregnant with her first child.

Barty surprisingly announced her retirement from tennis last March, just two months after she ended a 44-year wait for a home triumph at the Australian Open.

The 26-year-old, who won three grand slam singles titles during her career, revealed her pregnancy via an Instagram post on Friday.

"2023 set to be the best year yet. We are so excited for our new adventure. Origi already the protective big sister," Barty wrote, alongside an image of her dog Origi next to a pair of baby shoes. 

Barty's partner Garry Kissick also took to social media to share the news, posting a similar image featuring a baby-sized Liverpool kit with the caption: "Little Red, 2023".

Barty married professional golfer Kissick last July, six years after the pair met at the Brookwater Golf Club in 2016.

In addition to last year's Australian Open, Barty enjoyed singles success at Wimbledon in 2021 and the French Open in 2019, as well as winning the women's doubles title at the 2018 US Open alongside CoCo Vandeweghe.

Boris Becker has swiftly found work after his release from prison, with the German tennis great signed up for television commentary during the Australian Open.

The six-time grand slam singles champion, who took the Australian title in 1991 and 1996, will be part of German Eurosport's team for the season's opening grand slam.

That was announced by the broadcaster on Tuesday, with Becker to co-commentate on big matches and present a 'Matchball Becker' analysis segment twice a day.

Becker, 55, has worked for Eurosport in previous years, as well as being a regular on the BBC's coverage of Wimbledon, a tournament he won three times.

He was released from jail in December, eight months into a two-and-a-half-year sentence handed down as punishment for hiding £2.5million worth of assets and loans to avoid paying debts when he was declared bankrupt in 2017.

Becker, a former coach of Novak Djokovic, reportedly spent the first few weeks of his sentence at Wandsworth Prison in London before being moved to the low-security Huntercombe prison in Oxfordshire in May.

In an interview with Sat.1 after his release, Becker spoke of his experience, saying: "When the cell door closes, the whole world collapses. This is the loneliest moment I've ever had.

"There is only you with your thoughts. There's a carousel in your head, of course. You try to breathe calmly. I was afraid, I didn't cry.

"I believe I rediscovered the human in me, the person I once was. I've learned a hard lesson. A very expensive one. A very painful one."

Chris Evert has backed her long-time rival and friend Martina Navratilova to win her latest cancer battle.

American tennis great Evert, who completed her own course of chemotherapy treatment in May after being diagnosed with ovarian cancer, said Navratilova's "strength and resilience" would stand her in good stead.

Navratilova has been diagnosed with throat and breast cancer, she announced on Monday. The Czech-American successfully underwent treatment for breast cancer in 2010 and has said the condition is "serious but still fixable" this time.

Evert's battles with Navratilova in the 1970s and 1980s provided one of the all-time great tennis rivalries.

Both women ended their careers with 18 grand slam singles titles, with Navratilova triumphing a record nine times at Wimbledon. Only Steffi Graf (22) and Serena Williams (23) have won more singles majors among women in the Open Era.

Evert posted on Twitter: "Thinking of @Martina today and supporting her journey, like she did mine, with love and prayers. This is a woman who takes on challenges with strength and resilience…You got this, Martina."

Former US Open champion Tracy Austin sent "prayers and hugs", adding: "Don’t know too many stronger, I know you got this my friend."

Navratilova's long-time former doubles partner Pam Shriver added: "@Martina knows how to put together a winning team. While the news today is difficult, Martina understands how to compete, and take care of herself.

"Her loving family and many friends are ready to support her journey one day at a time. You have this partner!"

Ons Jabeur, who was runner-up at Wimbledon and the US Open last season, said she was "sending my love and my support".