Alexander Zverev insists his latest split from a high-profile coach ended on amicable terms after David Ferrer cut ties with the US Open finalist.

Spaniard Ferrer's decision to walk away leaves Zverev yet again, now at the age of 23, looking for a coach with whom he might establish a long-term partnership.

The German ditched former world number one Juan Carlos Ferrero in early 2018, after six months together, claiming the coach had been "very disrespectful" to other members of his team.

He then linked up with Ivan Lendl in August 2018 but that lasted just under a year, with Zverev reportedly criticising the eight-time grand slam winner's focus.

This time, Zverev and former world number three Ferrer have not hinted at any animosity or disagreements.

They teamed up in July 2020, and Zverev said of their break-up: "I would like to thank David for the months we have shared, the times on and off the court, wishing him only the best in the future.

"I also want to thank his family for giving me the chance to spend precious weeks with David during these difficult times. I have tremendous respect for the way David played and coaches tennis."

Ferrer helped Zverev battle through to the US Open final in September, where he led by two sets but was ultimately beaten by Dominic Thiem.

Zverev also won a pair of titles in Cologne in October and reached the final of the Masters 1000 event in Paris.

But they are going their separate ways as the new season begins, with the Australian Open just weeks away.

Ferrer said: "At the end of the year, a decision had to be made, I spoke with Sascha [Zverev] and told him that I preferred not to continue, that we were not going to continue next season. Not for anything special, I just didn't think it was time."

Speaking to tennis website Punto de Break, Ferrer added: "Absolutely nothing has happened between us, everything is still fine, in fact I am very grateful to him for the opportunity he gave me to travel with him during that stretch of the season.

"During those months we had a good coexistence, everything was perfect."

Carlos Sainz compared Ferrari and McLaren to LaLiga heavyweights Real Madrid and Barcelona, and is confident of a successful transition to the Scuderia. 

The Spaniard spent the past two seasons at McLaren, making the podium on two occasions, but is Ferrari-bound for 2021, replacing Sebastian Vettel.

Sainz spoke about how the objective for both teams is to cut the gap to dominant Mercedes, while he feels the fact he will have raced for both teams proves he is doing something right in his career.

Asked by AS if racing for Ferrari is like playing for Real Madrid, the team Sainz supports, he replied: "It's one way of saying it…but McLaren is Barca, which is also a very good team to be on. 

"It cannot be compared, because in addition both are in a restructuring to try to dethrone Mercedes in the future. 

"But they are the two best teams in history and when you go from one to the other it means that you are doing something right in Formula One."

At Ferrari, Sainz is joining a team where the pressure is always on to be a success and internal politics have historically always been a lingering presence in the background.

But Sainz is confident of being able to bring a harmonious atmosphere like the one he was part of at McLaren.

"That I managed to do it at McLaren means I can do it at Ferrari. If I could create a good team, generate good dynamics at McLaren, why not do it at Ferrari? I can do it," he added. 

"I like the people out there, I like Mattia [Binotto, Ferrari team boss] and I like what I see, what we have talked about. 

"There was no hesitation when it came to signing the contract and going forward. In my head there is no possibility that this environment and similar situation cannot be generated. 

"If I could at McLaren, I can at Ferrari."

Sainz's predecessors at Ferrari Vettel and Fernando Alonso arrived with huge reputations as two of the most gifted drivers of their generations and with world titles to their name.

Neither man was able to end Ferrari's wait for a champion dating back to 2007 but Sainz believes it is wrong to judge their success at Maranello based on titles.

"They leave with a few victories and podiums, if you call that going empty…I only have two podiums," he said. 

"Are they leaving without a championship? Yes. But the same has happened to nineteen drivers, every season for the last 10, when Red Bull or Mercedes have dominated. 

"There are nineteen drivers a year who have gone empty, but I do not include those who have raced for Ferrari. Nobody leaves Ferrari empty."

Los Angeles Lakers star LeBron James condemned the scenes in Washington, D.C. and shared the feeling that the response by law enforcement could have been far worse had the perpetrators been black people.

On Wednesday, a large number of violent protestors stormed the US Capitol after descending on the city for a rally held by Donald Trump, who has repeatedly claimed, without evidence, his presidential election loss to Joe Biden was fraudulent.

Five people are confirmed to have died and dozens arrested after appalling scenes at the seat of democracy in the United States on the day the electoral college certified Biden's victory, with some individuals able to force access into private offices and take pictures in the chair of vice president Mike Pence while members of congress were forced to flee under escort.

Tear gas was used in the Capitol Rotunda as part of non-lethal means to disperse the crowd, and Washington Wizards star Russell Westbrook claimed the outcome would have been "totally different" had the vast majority of aggressors been African-American.

Team-mate Bradley Beal said, compared with the police handling of Black Lives Matter protests last year, the response lacked the same "sense of urgency".

Philadelphia 76ers coach Doc Rivers shared that sentiment, saying: "It basically proves the point about a privileged life in a lot of ways. I'll say it because I don't think a lot of people want to: could you imagine today if those were all black people storming the Capitol and what would have happened?"

And James, who hit 27 points, six rebounds and 12 assists in the Lakers' 118-109 loss to the San Antonio Spurs on Thursday, said the black community has endured a hard week following the Capitol riots and the news that the police officer who shot and paralysed Jacob Blake in Wisconsin in August will face no charges.

"Obviously, the last few days have been very, very tough on anybody in the black community," James said.

"We got the news in Memphis with the Jacob Blake announcement and the cop being let off and then seeing what happened in our national capital, inside the Capitol.

"We live in two Americas. That was a prime example of that yesterday, and if you don't understand that or don't see that after seeing what you saw yesterday, then you really need to take a step back, not even just one step, maybe four or five or even 10 steps backwards.

"Ask yourself: how do you want your kids, or how do you want your grandkids, how do we want America to be viewed as, how do we want to live in this beautiful country? Because yesterday was not it.

"Being part of a household with three kids, two boys, a daughter, a wife, a mother-in-law, so many black folks in my household during that time and it's on the TV, couldn't help but wonder if those were my kind storming the Capitol... what would have been the outcome? I think we all know."

The Los Angeles Lakers' four-game winning streak was snapped in the NBA on Thursday, while the Philadelphia 76ers also fell.

Despite a double-double of 27 points and 12 assists from LeBron James, the Lakers were beaten by the San Antonio Spurs 118-109.

Anthony Davis also had 23 points and 10 rebounds, but the Lakers slipped to 6-3.

LaMarcus Aldridge posted a game-high 28 points for the Spurs.

After five straight wins, the 76ers fell to a 122-109 loss to the Brooklyn Nets.

Joel Embiid had a double-double of 20 points and 12 rebounds for the 76ers (7-2).

The Nets were without Kevin Durant (quarantine) and Kyrie Irving (personal reasons), but Caris LeVert posted 22 points, 10 assists and seven rebounds as they improved to 5-4.

Lillard lifts Trail Blazers, Doncic dominates

Damian Lillard's 39 points, seven rebounds and seven assists saw the Portland Trail Blazers past the Minnesota Timberwolves 135-117.

Luka Doncic dominated with 38 points, 13 assists and nine rebounds as the Dallas Mavericks overcame the Denver Nuggets 124-117 after overtime.

Andre Drummond had a double-double of 22 points and 15 rebounds as the Cleveland Cavaliers edged the Memphis Grizzlies 94-90.

Terrible Timberwolves

After back-to-back wins to start the season, the Timberwolves have suffered six straight losses. Malik Beasley struggled against the Trail Blazers, going three-of-13 from the field for 12 points in 28 minutes.

Cool Jokic

Nikola Jokic forced overtime for the Nuggets against the Mavericks with a long two. He finished with 38 points and 11 rebounds in the overtime loss.

Thursday's results

Brooklyn Nets 122-109 Philadelphia 76ers
Cleveland Cavaliers 94-90 Memphis Grizzlies
Portland Trail Blazers 135-117 Minnesota Timberwolves
San Antonio Spurs 118-109 Los Angeles Lakers
Dallas Mavericks 124-117 Denver Nuggets

Clippers at Warriors

The Los Angeles Clippers (6-3) and Golden State Warriors (4-4) meet for the second time in three days on Friday. The Clippers claimed a 108-101 victory on Wednesday.

Steve Nash labelled Joe Harris "a stud" after he helped the Brooklyn Nets beat the Philadelphia 76ers in the NBA on Thursday.

Harris was 11-of-19 from the field and six-of-nine from three-point range for 28 points in 30 minutes in a 122-109 victory.

The Nets were without Kevin Durant (quarantine) and Kyrie Irving (personal reasons), but Harris delivered off the bench.

Nash hailed the 29-year-old for his performance after the Nets improved to 5-4.

"Joe's a stud. He makes shots, he makes plays, he battles physically, defends, rebounds, he does a bit of everything," he told a news conference.

"He's not just a shooter. He makes other plays and makes his team-mates better because of his energy, effort and shot-making."

Durant and Irving are set to be absent again when the Nets face the Memphis Grizzlies on Friday.

A report claimed Irving simply did not want to play against the 76ers (7-2), but Nash dismissed those suggestions.

"I haven't spoken to him yet. I can't really comment because I haven't spoken to him and it's personal reasons so it'd have to come from Kyrie, but I don't believe that to be the case," he said.

Kevin Durant could return for the Brooklyn Nets against the Oklahoma City Thunder on Sunday, head coach Steve Nash said.

Durant missed Tuesday's win over the Utah Jazz and was expected to be absent for another three games after reportedly being exposed to someone who tested positive for coronavirus.

But the star may return early, although he will still miss the Nets' next two games – including Thursday's clash against the Philadelphia 76ers.

"I think Kevin's situation is that if he continues to test negative he can play Sunday," Nash told a news conference.

"That's all I have on that, but can't wait for Sunday to come."

The Nets will also be without another star, Kyrie Irving, against the 76ers due to personal reasons.

"I just found out. I just sent him a message in the last half hour and I haven't heard back yet," Nash said.

"But obviously thinking about him and hope all is well. It's a private matter."

Durant is averaging 28.2 points, seven rebounds and 4.8 assists per game for the Nets (4-4) this season.

Irving, meanwhile, is averaging 27.1 points, 6.1 assists and 5.3 rebounds.

Lonzo Ball is looking forward to taking on his brother LaMelo Ball when the Pelicans face the Charlotte Hornets on Friday - but getting New Orleans back on track is his primary concern. 

The Pelicans are 4-4 after suffering back-to-back narrow defeats against the Indiana Pacers and the Oklahoma City Thunder, while the Hornets ended a three-game losing skid by beating the Atlanta Hawks on Wednesday, improving to 3-5. 

LaMelo was the third overall pick in the 2020 NBA Draft and the rookie is already pushing for a spot in Charlotte's starting lineup, averaging 12.1 points, 5.3 rebounds and 4.9 assists through his first eight games in the league. 

In his fourth appearance, LaMelo had 22 points, eight rebounds and five assists in a 118-99 victory over the Dallas Mavericks. He became first rookie to post such a stat line (at least 20 points, eight rebounds and five assists) within their first four games in the league since Lonzo in 2017, and only the fifth since 1985-86 - Kevin Durant, Grant Hill and Lloyd Daniels the others to achieve the feat. 

Eight games into his NBA career, Lonzo was averaging 9.1 points, 6.8 rebounds and 6.6 assists from eight starts for the Los Angeles Lakers – the last of which saw him fail to score a single point in a loss to the Portland Trail Blazers. 

The game between the Pelicans and Hornets will be broadcast nationally in the United States but Lonzo does not intend to let a family reunion detract from greater objectives. 

"I think it's gonna be a lot of fun. It's our first time matching up in a real game, but I think it's gonna be an opportunity to just get back on track. We've lost the last two so we want to turn it around starting tomorrow," said Lonzo. 

"It's just about getting the win. It'll be cool seeing him out there and everything but he's gonna do what he can for his team and I'm gonna do what I can for my team and go from there." 

Asked if he was planning to treat LaMelo to some trash talk, he added: "No, I'll just play my game. Wherever coach puts me I'll do the best I can to get stops for my team and push the break the other way."

Despite spending their formative years together, Lonzo may be in for a surprise when he finally faces up to LaMelo having played minimal one-on-one during their youth.

"Not really too much one-on-one; a lot of two-on-twos, three-on-threes, though, pretty much our whole life," he said.

"One-on-one I was just always a little too big for him. As far as playing in the back yard, we played three-on-three pretty much every day. We always went at it and I think you see that in his game. He's not afraid of anybody. He's always played up and it's always been that way for him."

Lonzo and LaMelo enjoyed a single season as team-mates alongside their other brother LiAngelo – who has reportedly signed a contract to play in the upcoming G League season – during high school at Chino Hills in 2015-16, going 35-0 and winning a state championship.

"It was a lot of fun. We went undefeated that year. It was the only time we all got to play together in high school and we made the most of it," said Lonzo.

"It was just a fun time all around, being with them before I took off on my journey and they went their ways as well."

While Lonzo spent a year at UCLA before being drafted second overall by the Lakers in 2017, LaMelo opted against playing in college.

He turned professional and played in Lithuania and Australia either side of participating in the Junior Basketball Association - a league that was set up by his father LaVar Ball to offer an alternative to college.

"Everybody has to find their own way. Obviously, I went the more traditional route, he didn't, but at the end of the day we both ended up where we wanted to be," said Lonzo.

"Hard work definitely pays off. No matter who you are, you put your mind to something and you can do it. I really believe that. It worked for me, it worked for him, so that's what I'd tell kids growing up today as well."

Now the pair are on the same stage, Lonzo declared: "It just shows all the hard work paid off ... and we both ended up where we wanted to go."

Francisco Lindor's time in Cleveland has come to an end, as the Indians moved the four-time All-Star to the New York Mets in a blockbuster six-player trade announced on Thursday. 

The Mets will also receive starting pitcher Carlos Carrasco in the deal, with Cleveland getting infielders Amed Rosario and Andres Gimenez and a pair of prospects in pitcher Josh Wolf and outfielder Isaiah Greene. 

Lindor has been one of the game's premier shortstops, and the face of the Cleveland franchise, since breaking into the majors in 2015. The 27-year-old was the runner-up in voting for the American League's Rookie of the Year in 2015 and has won two Silver Slugger awards as well as a pair of Gold Gloves during his six-year career. 

The Puerto Rico native is set to be a free agent after this season, however, and an inability to agree to terms on a contract extension forced Cleveland to field offers from interested teams. 

Lindor joins a Mets organisation with grand designs under new owner Steve Cohen and who have been one of the more aggressive teams this offseason. New York previously added catcher James McCann and reliever Trevor May in free agency, while pitcher Marcus Stroman accepted an $18.9million qualifying offer to return. 

A career .285 hitter, Lindor has averaged 29 home runs, 86 RBIs and 21 steals over his six major league seasons. 

The Mets also add a valuable piece to the rotation in Carrasco, who went 88-73 with a 3.77 ERA in 11 seasons with Cleveland. The 33-year-old right-hander won 35 games between the 2017 and 2018 seasons before missing most of the 2019 campaign when diagnosed with leukaemia. 

Carrasco successfully fought off the disease to make 12 regular-season starts in 2020, going 3-4 with a 2.91 ERA and winning a second straight AL Comeback Player of the Year award. 

Rosario is the most experienced of the players Cleveland got in return and figures to slot in as Lindor's replacement at shortstop. The 25-year-old's last full season in the majors was a solid one as he batted .287 with 15 homers, 72 RBIs and 19 stolen bases. 

Gimenez, 22, made his major league debut last season and hit .263 with three homers and 12 RBIs in 49 games. 

Wolf and Greene were ranked as the Mets' number nine and number 10 overall prospects by MLB.com. Wolf was a second-round pick by New York in 2019, while Greene was taken in the second round of the 2020 draft and has yet to make his professional debut.

Dayana Yastremska says she is "astonished" after the world number 29 was provisionally suspended for failing an out-of-competition doping test.

The International Tennis Federation (ITF) on Thursday revealed Yastremska was charged on December 22, having tested positive for mesterolone metabolite in a sample taken on November 24.

Ukrainian Yastremska, who reached a career-high 21st in the rankings 12 months ago, says she is not guilty of any wrongdoing and will do all in her powers to clear her name.

The 20-year-old posted on Twitter: "I firmly state that I have never used any performance-enhancing drugs or any prohibited substances.

"I am astonished and under shock, particularly given that two weeks prior to this test - on 9 November 2020 - I tested negative at the WTA event in Linz. After this last tournament of the year, I stopped practising to rest prior to the start of the new season.

"Only a very low concentration of mesterolone metabolite was detected in my urine. Given that low concentration and given my negative test two weeks earlier, I have received scientific advice that the result is consistent with some form of contamination event.

"Besides, I have been informed that this substance is meant for use as medication by men and that women are advised not to use it due to the adverse effects it causes."

Yastremska said she was "resolutely determined to do everything to clear my name".

Rising star Yastremska has three WTA singles titles to her name.

Sofia Kenin and Coco Gauff both made it through to the second round of the Abu Dhabi Women's Tennis Open on a day of few shocks. 

Seven of the nine seeds in action on Thursday advanced, with only Marketa Vondrousova and Jennifer Brady falling by the wayside. 

Those upsets came despite Vondrousova and Brady each winning their opening sets - against Hsieh Su-wei and Tamara Zidansek respectively - the latter racing through 6-0 in the first before being reeled back in. 

Kenin and Gauff had no such problems, however. 

But top seed Kenin - the 2020 WTA Player of the Year - had to stay patient as she took down 789th-ranked Yang Zhaoxuan 7-6 (7-4) 6-2. 

The first set lasted more than an hour and saw Kenin face five break points, defending each of them, with another 11 Yang opportunities following in the second, although the world number four proved more clinical en route to victory. 

"It was the first match, obviously a bit of nerves, I had to find my groove," Kenin said afterwards. "Conditions weren't easy, it was quite windy.

"The first set was tough for me. I couldn't find the ball, I guess." 

Gauff was comfortable throughout, meanwhile, swatting aside Ulrikke Eikeri 6-0 6-1 to tee up a meeting with Maria Sakkari. 

Elina Svitolina, Karolina Pliskova and Aryna Sabalenka each also progressed in two sets, as did Garbine Muguruza, overcoming a potentially tricky hurdle in the form of Kristina Mladenovic. 

Muguruza was a 6-2 6-4 winner and afterwards said: "I was trying to do my game, dominating, not letting her dominate the point. 

"It's the first match of the year, it's a little bit tricky to get the feeling, but I'm happy with the win." 

It was never going to be easy for the Toronto Raptors, not when you are living out of hotels and temporary residences more than 2,000 miles from your home city. Not when you dwell in by far the most top-heavy division in the Eastern Conference.

Still, the way the 2018-19 NBA champions have performed more like a bottom-feeding also-ran than a presumed title contender during the nascent stages of a challenging 2020-21 season is at least a cause for concern. And the difficult circumstances the Raptors find themselves under, playing their home games in Tampa, Florida, after being forced southward by travel restrictions by the Canadian government, does not reasonably explain all their early problems. 

It is not the sole reason Toronto has been among the league's most inept scoring teams thus far, ranking 26th in offensive rating and dead last in field goal percentage. It is not why the Raptors have been routinely steamrolled in the second half of games during their 1-6 start (their sixth loss of last season did not come until their 21st game, by the way).

No, there's a bit more to it than that. And while it is certainly not time to press the panic button just yet, there are a few areas the Raptors clearly need to improve on if they are to at least extend their current seven-year streak of playoff appearances. 

THE SHOTS ARE NOT FALLING, ESPECIALLY FROM LONG DISTANCE 

The 3-point shot has always been a big part of the Raptors' game since Nick Nurse took over as head coach, as they ranked sixth in the NBA in 3-point rate (the ratio of 3-pointers attempted to total field goal attempts) last season and 10th during their 2018-19 championship campaign. So far in 2020-21, nearly half (49.2 per cent) of Toronto's shots have come from behind the arc – the highest total in the league. 

The difference is this Raptors are not hitting those shots at nearly the same proficiency as before. Toronto's 34.2 success rate ranks 24th in the league. The Raptors finished no lower than sixth in either of the past two seasons. 

In 2019-20, the Raptors had six players with at least three 3-point attempts per game shoot 38 percent or better from long range, tied with Detroit for the most in the NBA. Only three current players (Fred VanVleet, Chris Boucher, Matt Thomas) can make that claim so far this season. 

Two players who accomplished that feat in 2019-20, Marc Gasol and Serge Ibaka, have moved on. Aron Baynes, a 35 percent 3-point shooter over the past two seasons, was signed with the intent to fill the void, but he is 3-of-16 on triple attempts thus far. Holdover OG Anunoby, just weeks removed from signing a four-year, $72million extension, is 12-of-41 (29.3 percent) after hitting at a 39 percent clip in 2019-20. 

WHERE HAVE YOU GONE, PASCAL SIAKAM? 

Siakam's well-documented struggles in Toronto's seven-game loss to Boston in last season's Eastern Conference semi-finals may not have been a blip on the radar.

The Celtics masterfully neutralised the forward by deploying the smaller Jaylen Brown as his primary defender, and teams have been successfully following that blueprint during the early stages of this season. 

The plan is working so far, too. Often drawing defenders with the length and athleticism to give him problems (Philadelphia's Ben Simmons and San Antonio's Rudy Gay were particularly effective), Siakam is simply not getting to the rim with the same frequency as past years, and (see below) has been among the least efficient players of his size when doing so.

LOWEST FG PERCENTAGE AT THE RIM – PLAYERS 6'9" OR TALLER - IN 2020-21 SEASON (minimum 100 minutes played) 

Isaiah Stewart, Det .478 
Pascal Siakam, Tor .488 
LaMarcus Aldridge, SA .500 
Brook Lopez, Mil .500 
Jusuf Nurkic, Por .500 
Dwight Powell, Dal .500 

The Raptors have been outscored by an astonishing 63 points with Siakam on the court, an average of 10.5 per game that is eclipsed only by a pair of players from the likely lottery bound Timberwolves (D'Angelo Russell, Ed Davis) for the worst mark in the league. 

It has been a humbling start for the 2018-19 NBA Most Improved Player, and that frustration was no more evident than when he bolted straight to the locker room after fouling out late in a loss to the 76ers. Nurse benched him for the next game, which happens to be the only one the Raptors have won so far.

Siakam did look more like his old self in Wednesday's outing at Phoenix, when he put up 32 points and shot over 50 percent from the field for the first time this season. It goes without saying the Raptors need him to return to his All-Star form, as they were 19-1 when he scored 25 or more points in a game in 2019-20. 

LEADS ARE SLIPPING AWAY 

Six teams have lost multiple times when holding a double-digit lead in a game so far. The Rockets, Hawks, Wizards and Pistons have done so twice, the Grizzlies three times. The Raptors have five such losses through their first seven outings.

Starting well hasn't been a problem - Toronto is outscoring opponents by an average of 4.3 points in the first quarter, the second-best mark in the NBA behind only Milwaukee. Starting the second half well has been a real issue, however. The Raptors have been outscored by an average of 5.4 points in the third quarter, with only the Timberwolves and Cavaliers having been worse.

In contrast, the Raptors outscored foes by 4.3 points per game in the third quarter (fourth-best in the NBA) while going 53-19 last season. They ranked second in the league during their 2018-19 title run.  

So what's the reason for the dramatic drop-off? Is it because Toronto fields one of the league's older rosters? The Raptors are one of only three teams with two starters (Baynes and Kyle Lowry) aged 34 or older. One of the others is the Lakers, however, so there goes that theory. 

A lack of depth is the more plausible answer. The Raptors rank 27th in the NBA in bench scoring, though they also had one of the league's least productive second units last season. That was less of an issue in 2019-20 because the starting five was often so good. With Siakam, Anunoby and Baynes all underperforming thus far, it has quickly become a more pressing concern. 

THE BOTTOM LINE 

There's no cause for alarm yet for Toronto fans just yet regarding their snowbird team. If not for a few bad stretches, the Raptors could just as easily be 5-2 instead of 1-6, and a defense that is still among the NBA's better units has kept them in every game in spite of their inefficiencies on the other end. 

There is enough of a track record throughout the roster to suggest that the offense will come around. It needs to as well for a team that has been built on the premise of winning now and whose window may be closing soon.

Lowry, the Raptors' unquestioned heart and soul, is in the final year of his contract and turns 35 in March. Does team president Masai Ujiri consider moving him at the trade deadline if Toronto finds itself fighting for merely a playoff spot instead of a division title? 

The next two months should be very intriguing in Toronto. And Tampa as well.  

Roger Federer decided to miss the Australian Open because wife Mirka opposed having to spend a full fortnight in quarantine, a leading official has claimed.

It was widely assumed Federer's reason for skipping the upcoming grand slam related to the knee surgery he underwent last season.

He had hinted as much, and agent Tony Godsick referred to the knee rehabilitation when announcing in December that the Swiss great would not travel to Melbourne.

But Andre Sa, the head of player liaison at Tennis Australia, says Federer pulled out when it became apparent his wife and children would be holed up in their hotel accommodation for two weeks.

The players travelling to Australia must all quarantine to avoid any possible spread of COVID-19, but they are allocated five hours per day in which they can leave their rooms to train and practise with specified hitting partners.

Sa, a former top-20 doubles player, told Band Sports in his native Brazil that he discussed with father-of-four Federer the practicalities before the 20-time grand slam winner reached his decision.

"The main reason was the quarantine," said Sa. "I talked to him a month ago and he had two options. He could come with the whole family and do the quarantine.

"The problem is that Mirka and her children couldn't leave the room. They would have to stay 14 days in the room. The exception is only for players.

"He could go out, train and come back, but the family couldn't. Mirka did not approve the idea.

"The other option would be for him to come alone. Only there would be at least five weeks away from family and children. And then he said, 'Dude, 39, four kids, 20 grand slams. I'm no longer at the stage to be away from my family for five weeks.'"

Former world number one Federer has not played a tournament since losing to Novak Djokovic in the semi-finals of the Australian Open last year.

This year's edition of the grand slam has been delayed by three weeks to a February 8 start, due to factors tied into the pandemic.