Simona Halep has withdrawn from the Miami Open after aggravating a thigh injury.

Former world number one Halep was due to face Australia's Daria Saville in the round of 64 on Thursday but felt unable to contest the match.

Halep said she sustained a thigh injury during her Indian Wells semi-final defeat to Iga Swiatek the previous week and it caused her discomfort again while training on Wednesday.

The 30-year-old two-time major winner expects to sit out the Charleston Open and will miss the start of the Billie Jean King Cup.

In a tweet posted on her official Twitter account, Halep wrote: "While I was practising in Miami yesterday I felt a sharp pain in my left leg.

"I had been struggling with the thigh since my semi-final in Indian Wells and hoped it would improve, but I went for an MRI last night and unfortunately it showed a tear.

"My body needs time to heal and as a result I will be out of competition for three weeks. This means I have had to make the super tough decision to pull out of Miami, Charleston and Fed Cup [Billie Jean King Cup].

"While it feels like really disappointing news to share, I am keeping the confidence from my great start to the year and am motivated to do everything to be ready for the clay-court season.

"Thanks for your continued support through the highs and lows."

Lucky loser Harmony Tan will take Halep's place in the draw.

Naomi Osaka looked relaxed and composed as she eased to a straight-sets win at the Miami Open, and offered a clue as to why when speaking to reporters afterwards.

The 24-year-old revealed she has started seeing a therapist after her recent loss at Indian Wells, where she suggested a heckler had affected her performance.

Osaka was left in tears as she struggled to deal with someone apparently shouting "Naomi, you suck!" during her second-round defeat to Veronika Kudermetova.

She also withdrew from Roland Garros last year, citing mental health concerns.

However, the three-time grand slam champion produced a strong display in her first round encounter in South Florida to beat Astra Sharma 6-3 6-4 on Wednesday.

"I don't know if I'm allowed to say this, but I finally started talking to a therapist after Indian Wells. It only took like a year after French Open," she told reporters after her win.

"She kind of told me strategies and stuff. I realise how helpful it is. I'm glad that I have people around me that told me to, like, go in that direction.

"But, yeah, I was basically just remembering all the things that she told me to do, just to take deep breaths and reset myself when I need to."

The world number 77 revealed it was partly her sister, former professional player Mari Osaka, showing concern that led her to seek out therapy.

"I feel like I've been trying a lot of different things because I tend to internalize things, and I also want to do everything by myself," Osaka clarified, adding that her coach, Wim Fissette, had also encouraged her to do so.

Osaka believes she is now better prepared to handle a similar situation to Indian Wells should it arise, having realised it may have been the first time she has been heckled during a game.

"I think for me, the situation in Indian Wells, I've kind of thought back on it. I realise I've never been heckled. I've been booed, but not like a direct yell-out kind of thing. It kind of took me out of my element.

"I feel like I'm prepared for it now. I was kind of bracing myself before the match to just know that's a thing that could happen now. I think I just needed to change my mindset a little."

England's Six Nations performance has been labelled "incredibly disappointing" by Rugby Football Union chief executive Bill Sweeney.

Eddie Jones' side backed up a poor 2021 championship campaign with just two wins from five again, as their third-place finish lagged far behind France and Ireland.

A year-and-a-half out from the 2023 World Cup across the channel, England look unlikely to contend for the crown as they did in Japan in 2019.

"We are all, as an organisation, incredibly disappointed with what happened this year in the Six Nations," Sweeney told the media. "You'd expect more.

"To come away with fifth-place last year and two wins, and then going into this year's Six Nations feeling in good shape and expecting more, to only have a further two wins out of 2022 and come third was incredibly disappointing for us.

"We demand more in terms of our results and performances. Emotions have been running very high, it still feels quite raw. There is a great deal of frustration and disappointment."

Sweeney paid tribute to England supporters for their contributions, while stressing the team has still made progress under Jones in the last year.

"We saw a fantastic response from the fans during the Ireland game, one of the best examples of connecting with the team," he added.

"We understand why they're expecting more and feel not in a great place at the moment.

"We do feel there's been some real positive developments. We do feel we're on a path to the right direction. If you look at where we were 12 months ago: we're in a better place.

"It's a very tight-knit squad. There is a strong spirit. The players believe in [Jones] and believe he's taking them in the right direction.

"We're very excited by developments despite the fact we're coming out of a very difficult period. We know we're going to get better."

Ash Barty has not ruled out a return to professional tennis, saying "never say never" when asked if she could make a comeback in years to come.

The three-time grand slam winner announced her surprise retirement from the sport on Wednesday, less than two months after her home victory at the Australian Open.

At just 25, Barty is stepping away from the court at the peak of her career, and has teased the idea she could step into another sport entirely.

But speaking on Thursday, the reigning Wimbledon champion did not discount the possibility of returning to tennis down the line.

"You never say never," she said. "But it's a long way off at this stage."

Barty previously played cricket during a sabbatical between 2014 and 2016, and has been linked with a switch to golf in recent years too.

She shut down such suggestions as an immediate option, adding: "[I've] got to try and learn how to hit the middle of the club face before I can think of trying to get on the tour."

Elsewhere, Barty admitted that she would miss the competition of the WTA circuit, while praising fellow Australian Open champion Rafael Nadal for his staying power in the sport.

"I love the competition," she said. "That's what has driven me the most in my career, is that one-on-one competition and the thrill of the fight. I know that I'll miss it 100 per cent.

"But I'll be able to get the adrenaline in different ways. Those ways will remain to be seen. But I know that I've been so fortunate to have so many incredible moments on the court."

Unlike Nadal, Barty is bowing out of tennis early, and she respects the way the 35-year-old Spaniard, who also triumphed at Melbourne Park this year, has been able to stay at the top for the best part of two decades.

She said: "It's been an incredible career. His longevity in the sport has been undeniable. He's been amazing for the sport of tennis. For me as a fan to see him do that over such an extended period has been a pleasure."

Sebastian Vettel could be forced to sit out a second race after Aston Martin said he remained positive for COVID-19 and had not yet travelled to the Saudi Arabian Grand Prix.

The four-time world champion had been hoping for a significant upturn in his recent fortunes this season, but it has begun in disappointing fashion for the German.

He had to sit out last weekend's opener in Bahrain after testing positive for the coronavirus, and stand-in Nico Hulkenberg could be pressed into action again in Jeddah.

Vettel, 34, won his world titles consecutively from 2010 to 2013, and he joined Aston Martin ahead of the 2021 season.

Aston Martin said Vettel would be given until Friday to return a negative test, otherwise the team will plan without him for this weekend's racing.

The team said on Twitter: "Sebastian Vettel has not yet returned the required negative COVID test to fly to the #SaudiArabiaGP. Nico Hulkenberg will be in Jeddah to deputise for Seb if necessary. We will delay our final decision until Friday to provide Seb every opportunity to race."

Hulkenberg finished 17th in Bahrain, with Lance Stroll 12th, as Aston Martin failed to finish in the points.

Erik Spoelstra said his mid-game spat with Jimmy Butler showed the passion within the Miami Heat ranks and their unwillingness to tolerate slumping performances.

Coach Spoelstra and six-time All-Star Butler, along with Udonis Haslem on the Heat bench, appeared to exchange fiery words and gestures during a timeout as the Heat struggled against the Golden State Warriors.

Golden State bolted to a 69-50 lead after scoring the first 19 points of the third quarter, and amid this slide came the dispute within the Heat ranks.

Spoelstra slammed a clipboard down onto the court and confronted Butler before others attempted to separate the pair.

Allowing himself to joke after the game, which saw the Heat roar back to establish an 84-81 lead before crumpling to a 118-104 defeat, Spoelstra explained the incident.

"Everybody was wondering where the dinner plans were tonight after the game," he said, before answering more seriously.

"It was pretty clear, we have a very competitive, gnarly group, and we were getting our a***s kicked, and it's two straight games we were not playing to the level we wanted to play.

"Every person in that huddle was pretty animated about our disappointment at how we were playing."

This game followed a 113-106 loss to the Philadelphia 76ers, and the Eastern Conference-leading Heat's record now stands at 47-26.

Asked about whether the public bickering could have a lasting impact, Spoelstra said: "It won't, we have bigger things to accomplish, but we do want to play better, and everything has to be better across the board.

"It starts with our leadership, our veteran players have to lead, and then we just have to play better, play better to our identity and that's really all the discussions were.

"I know how it can look from the outside, but that is more our language than playing without passion or without toughness, or without multiple efforts and lifelessness.

"Everything that happened in the hall from then on, as we cut that 19-point lead, that's way more to our personality."

Spoelstra even hinted the flash point could have a positive impact.

"You can use moments during a season to catapult you. You can galvanise together over frustration and disappointment," he said. "Teams can also go the other way. I don't see that with our group. But we have needed a kick in the butt from these two games.

"These two games were disappointing to everybody. You see a competitive group that is not playing to the level or the standards we want to play at.

"Let's give credit to Golden State. We played with great passion to get back into the game, but they executed well, and they made some big shots."

Ash Barty insisted she would "never stop loving" tennis as the three-time grand slam winner kept everyone guessing about her next steps in life.

The 25-year-old announced a shock retirement on Wednesday, less than two months after triumphing at the Australian Open.

Barty hinted she would look to find a new role in sport, possibly in a playing capacity, and said she and boyfriend Garry Kissick had set a wedding date, but left it at that.

Speaking at a news conference in Brisbane, Barty said she had intended to reveal her retirement after playing for Australia in a Billie Jean Cup qualifying match in April.

However, reigning champions Russian Tennis Federation were recently excluded, due to the war in Ukraine, which meant the event was restructured and Australia did not need to play a qualifying tie. Barty consequently brought her announcement forward.

She said she had "given absolutely everything I could to this sport", and confirmed she has asked the WTA to remove her name from the world rankings the next time they are published.

Barty has retired as the world number one, with Iga Swiatek in pole position to succeed her. Results at the Miami Open, getting under way this week, will determine who tops the list when it is released on April 4.

"It's going to be an exciting time for the WTA Tour with the new number one," she said. "It will be a really cool period for them now."

Australian Barty, who is also the reigning Wimbledon champion, said of her career: "It's been a hell of a journey. I wouldn't change a thing and I certainly have no regrets."

She said winning the Australian Open in January had been "a brilliant way to finish", adding: "I'm excited for what's next, for my next chapter as Ash Barty the person, not Ash Barty the athlete."

Appearing alongside coach Craig Tyzzer, Barty said she had been practising on court even in the last fortnight.

"I hit as recently as 10 days ago," she said. "I'll forever be connected to tennis. I'll never stop loving the sport, I'll never stop hitting tennis balls. I just won't be doing it selfishly to progress my career, it'll be for different reasons."

Barty has played cricket at a high level before and is a keen golfer.

So could she look for a career in a sport other than tennis?

"I've seen some brilliant Photoshops as a jockey, lawn bowls," she said. "I love sport. I'm a sport nut, like a lot of Australians are; I'll be glued to it.

"I've always been an athlete in a sense of trying different things. But we will see how we go."

She is eager to share her tennis knowledge with youngsters in a coaching capacity, and appears to be relishing a quiet life away from the hustle of being a globe-trotting sports star.

Asked about her plans to marry Kissick, a trainee club golf professional, Barty said plans were in place, adding: "You have to wait and see."

Kevin Durant and Kyrie Irving delivered big performances, but the Memphis Grizzlies were unstoppable in the first half on the way to a 132-120 win over the Brooklyn Nets.

Irving finished with 43 points (15-of-27 shooting, six-of-11 from three) and eight assists, while Durant posted figures of 35 points (12-of-28 shooting, 10-of-10 from the free-throw line) with 11 rebounds, eight assists, two blocks and two steals.

But the Grizzlies would not be denied in front of their home fans, clicking on all cylinders early to jump out to a 76-62 half-time lead.

It was yet another stunning showing without MVP candidate Ja Morant who missed again through injury, with seven Grizzlies scoring double figures to pick up the slack.

Desmond Bane (eight-of-17 shooting) and De'Anthony Melton (eight-of-13 shooting) led the way with 23 points each, while Jaren Jackson Jr swatted away four shots as he continued his charge for Defensive Player of the Year.

With the win, the Grizzlies moved to 50-23 for the year, and an incredible 15-2 in games Morant has missed.

Warriors 'punk' the Heat

A day after Draymond Green said his Golden State Warriors were being "punked" in recent losses, they responded in style, beating the Miami Heat 118-104 without Green and injured star Stephen Curry.

In a game where Heat All-Star Jimmy Butler had to be physically separated from coach Erik Spoelstra during a time-out, the Miami defence simply could not get stops in the second half as tempers flared.

Jordan Poole shone yet again for the Warriors, scoring 30 points on 10-of-18 shooting, going three-of-seven from long range, while rookie Jonathan Kuminga, All-Star Andrew Wiggins and bench player Damion Lee chipped in with 22 points each.

Ayton and the Suns shine in Minnesota, Davion dominates

A 42-point fourth quarter capped off a terrific 125-116 comeback win for the Phoenix Suns on the road against the Minnesota Timberwolves.

Trailing 64-51 at the halfway stage and by five at three-quarter time, the Suns got 11 points from centre Deandre Ayton down the stretch to cap off a big 35-point (15-of-24 shooting), 14-rebound performance.

Devin Booker controlled the contest for the Suns, scoring 28 points on only 15 field goal attempts, going 13-of-16 from the free throw line while also dishing out seven assists.

Meanwhile, rookie top-10 pick Davion Mitchell starred in the Sacramento Kings' 110-109 away win against the Indiana Pacers, scoring 25 points on 10-of-15 shooting and collecting seven assists in arguably his best game as a professional.

Joel Embiid scored 30 points and had 10 rebounds, three steals and three blocks for the Philadelphia 76ers in their 126-121 win over a Los Angeles Lakers side who were without LeBron James.

Nick Kyrgios maintained his impressive form from Indian Wells to prevail in his first-round match with Adrian Mannarino at the Miami Open.

Former world number 13 Kyrgios is ranked outside the top 100, but delivered a reminder of his quality at Indian Wells by reaching the quarter-finals.

He claimed a top-10 win over Casper Ruud before losing to Rafael Nadal in three sets, and the Australian will now face Andrey Rublev in South Florida after seeing off Mannarino in straight sets.

Kyrgios took the first in a tie-break and broke the Mannarino serve late in the second to clinch a 7-6 (7-3) 6-3 win.

There was a huge disparity in the winner count, Kyrgios hitting 33 to Mannarino's 15, and it was that extra firepower that made the difference in the closing stages.

A fine backhand winner gave Kyrgios break point, which he converted with a confident forehand at the end of an absorbing rally to take a 5-3 lead. The break was then consolidated as Kyrgios sealed his triumph with an ace down the middle.

Also into the second round is Jack Draper, who overcame Gilles Simon to claim his first ATP Masters 1000 win and set up an all-British clash with Cameron Norrie.

Brandon Nakashima will meet American compatriot Frances Tiafoe after his first main-draw win in Miami over Soonwoo Kwon.

Thanasi Kokkinakis beat Richard Gasquet in straight sets while there were also wins for David Goffin and Borna Coric.

Tyreek Hill hailed the start of a new beginning with the Miami Dolphins as he thanked the Kansas City Chiefs for believing in him following Wednesday's blockbuster trade.

The four-time All-Pro wide receiver and member of the NFL 2010s All-Decade Team was traded to Miami for five draft picks, Hill receiving a four-year, $120million contract, with $72.2m guaranteed, from the Dolphins.

Hill, who is one of the fastest players in the history of the league, has been the centrepiece of the NFL's most explosive offense since Patrick Mahomes took over as the Chiefs' starting quarterback in 2018.

He has four 1,000-yard seasons in a six-year career, which has included 56 receiving touchdowns.

Hill will hope to have a transformative impact for the Dolphins and quarterback Tua Tagovailoa, who threw for just nine touchdowns with five interceptions across Miami's 8-1 run to end last season.

In a post on social media, Hill expressed his excitement at joining the Dolphins, before turning his attention to a Chiefs franchise that selected him in the fifth round of the 2016 draft.

"Today starts a new beginning. I'm very excited to be joining the Miami Dolphins and get to work," Hill, who lives in Miami during the offseason, wrote.

"However, it's hard thinking about the memories, people, and fans that made my time in Kansas City so great. To my family and especially my kids, thank you for being my biggest supporters. Daddy loves you! 

"I'm grateful to those who joined me in giving back to the Kansas City community through the Tyreek Hill Family Foundation. From college scholarships, youth football camps, funding the first youth mental health navigator at Marillac, donating supplies to the homeless, and visiting with kids in the hospital, we couldn't have made the impact without all of you. 

"Thank you to the Chiefs organisation for believing in me. I'll never forget getting the call in 2016 that my dream to play in the NFL was coming true. I worked hard every day to show my appreciation for you taking a chance on me. To coach [Andy] Reid, coach [Eric] Bieniemy, and coach [Greg] Lewis, thank you for what you have taught me not only about football but about life. 

"Thank you Pat, [Travis] Kelce, Demarcus [Robinson], and [Gehirg] Dieter along with all my team-mates. I'm proud to have taken the field with each of you.

"You are what made each day worth it. We are brothers for life! To the fans, thank you for your support. Playing for you has been one of the greatest things I have done in my life. Your energy, passion and loyalty for the team is indescribable. It was an honour to play in front of you. 

"Kansas City will always hold a special place in my heart. Cheetah out!"

US Open champion Emma Raducanu is not planning on replicating Ash Barty after the world number one retired at the age of 25.

Barty announced her retirement on Wednesday less than two months after winning the Australian Open, saying she has accomplished all she set out to in the sport.

There has since been an outpouring of respect and admiration for Barty, with the prevailing sentiment being that it is a great loss for tennis.

Raducanu burst onto the scene last year with a run to the fourth round at Wimbledon that was followed by a remarkable triumph at Flushing Meadows, making history at the age of 18 in becoming the first player to win a grand slam as a qualifier in the Open Era, doing so without dropping a set.

And she is planning on staying on the WTA Tour for many years to come.

"For me, I want to be in the game as long as possible," Raducanu said.

"I'm only 19. I've just come on tour, which is pretty young.

"I want to be in the game till I'm in my 30s. We'll see what happens and how long I can last, to be honest."

Reflecting on Barty's career, one in which she took a break from the sport in 2014, briefly playing professional cricket, before returning in 2016, Raducanu added: "If you get oversaturated with one thing, it's not healthy with anything you do.

"I feel like that just shows, if you take time off, you come back, you're hungry, you're ready. 

Kyrie Irving will make his Brooklyn Nets home debut for the season on Sunday after changes to New York's vaccine mandate come into effect on Thursday, according to reports.

Irving, 29, has only played 19 games this season after deciding not to get vaccinated, but has excelled when in the line-up, averaging 27 points, five rebounds and five assists.

Despite athletes playing for New York teams requiring vaccination to play, visiting players were not subjected to the same requirements, with this move seen as 'levelling the playing field', as put by The Athletic's Shams Charania.

With the new exemption for in-town athletes and performers kicking in on Thursday, it means Irving will be eligible to suit up for the Nets' Sunday fixture against the visiting Charlotte Hornets.

It is important timing for the Nets as their positioning in the play-in tournament means they likely will need to win a home game to earn their way into the playoffs.

Two of the top-ranked players on the WTA tour have spoken about world number one Ash Barty's shock retirement, with Danielle Collins calling it "badass".

Barty announced she had retired through a post on her Instagram account, where she had a sit-down interview with former Australian tennis player Casey Dellacqua about her decision to walk away.

In her interview, Barty discussed accomplishing the goals she set out for herself in her tennis career, capped off with wins at Wimbledon and this year's Australian Open, as well as having other dreams she would like to work towards.

Barty, 25, has played professional cricket in Australia's Big Bash League, and has been linked with her beloved Richmond Tigers if she were to try her hand at Australian Rules football.

She is also recently married, and has discussed her desire to start a family.

Collins, currently the world number 11, spoke about how incredible it is that Barty is able to walk away at such a young age, with so many accomplishments under her belt.

"I am a little bit surprised because I think at 25 and being at the top of her game and in achieving everything that she's achieved and being so young she would certainly continue to achieve what she's been achieving," Collins said.

"But I think it really speaks to the way that our game empowers women, because how many other professions would you be able to retire at 25? 

"I mean, this is incredible, it's so badass, and I really have a lot of respect for Ash making the decision to do what's best for her, and to live out her life on her terms. It's really special."

Rising star and world number two Iga Swiatek also weighed in, saying her first reaction was an outpouring of emotion about what a loss it was for the game of tennis.

"Well, I mean, it is so fresh and it's so sudden that it is something that I need to digest," the 20-year-old said.

"I cried for like 30 minutes, actually, when she posted that video and that interview. 

"It's very hard to describe it because on one hand… if you know Ash, it's not a surprise at all, because she's like that kind of person who's looking for challenges also in other aspects of life. 

"I mean, you can see that she's pretty confident with her decision. But on the other hand, it's new for me to see athletes retiring so early. 

"I'm pretty new on tour and I feel like I wanted to play more matches against Ash, and also compete against her and have a chance to actually understand how she plays and how she uses the different skills that she has. 

"I mean, for me, I feel kind of sad that I'm not going to be able to do that because I think it would be a great rivalry. And also, she's a great person to look up to and to kind of chase. 

"But I'm also happy for her, and I think she's really brave that she made that decision because there would be many people who, I don't know, kind of stay in this place because you were first in the world.