John and Patrick McEnroe have led the angry backlash against Roger Federer after the Swiss legend announced his shock withdrawal from the French Open on Sunday.
Federer has left the tennis world stunned after pulling out of the clay-court grand slam a day after winning a tough third-round match.
'RIDICULOUS': Insane Rafa Nadal moment stuns tennis world
'SHAME ON THEM': Roger Federer in 'embarrassing' French Open act
The Swiss legend, who turns 40 in August, said he wants to save his body for the grass-court season and a shot at a 21st grand slam title at Wimbledon.
"After discussions with my team, I decided that I should withdraw from the French Open today," Federer said in a statement released by the French Tennis Federation on Sunday.
"After two knee operations and more than a year of rehabilitation, it's important that I listen to my body and not rush back into competition."
However the decision has not gone down well in the tennis world, with American greats John and Patrick McEnroe criticising Federer's move.
“I understand it, but I don’t like it. It’s just not a great look to pull out of a tournament in the middle," Patrick McEnroe told the New York Times.
“It’s one thing if you sprain an ankle badly and finish a match on adrenaline. Those things happen. But it’s another thing when you kind of go into a tournament knowing that you probably aren’t going to be able to really finish the tournament.
“Roger can’t expect that he’s going to play the French Open and not have some physically demanding matches in the first three or four rounds. That’s kind of inevitable.
“Look, he’s trying to get himself ready to make a run at Wimbledon, which I believe he’s done. And a lot of people say he’s Roger Federer. He can do whatever he wants. He’s earned this right, and I understand that, but I still don’t like it.”
John McEnroe was also gobsmacked, telling NBC: “Perhaps Roger might have done the magnanimous thing and defaulted match point up (against Koepfer) … but that’s easy for me to say from Malibu."
Fans were also left fuming over Federer's withdrawal, with some labelling the decision a "disgrace".
Roger Federer targeting fairytale Wimbledon title
Federer battled over three and a half hours until nearly 1am on Sunday morning to reach the last 16 with a 7-6 (7/5), 6-7 (3/7), 7-6 (7/4), 7-5 win over 59th-ranked Dominik Koepfer.
He was due back on court on Monday to tackle Matteo Berrettini for a place in the quarter-finals.
However, having undergone two knee surgeries in 2020, the Swiss star had admitted there were doubts over whether he'd make it.
Federer is playing only his third tournament since last year's Australian Open and has always said Wimbledon is his main goal.
"We go through these matches ... we analyse them highly and look on what's next and we'll do the same tonight and tomorrow," he said.
"Because I need to decide if I keep on playing or not, or is it not too much risk at this moment to keep pushing or is this just a perfect way to just take a rest."
Federer is scheduled to play the warm-up grass court tournament in Halle beginning on June 14, the day after the French Open ends.
The 39-year-old, who made his Roland Garros debut in 1999 and was champion in 2009, was playing a night session for the first time in his third round tie.
However, the almost empty 15,000-capacity Court Philippe Chatrier was eerily silent due to a Covid-19 curfew.
It is likely that this was Federer's final appearance at the tournament. His return this year was only his second participation since 2015.
"The Roland Garros tournament is sorry about the withdrawal of Roger Federer, who put up an incredible fight last night," said Guy Forget, the tournament director.
"We were all delighted to see Roger back in Paris, where he played three high-level matches. We wish him all the best for the rest of the season."
Watch 'Mind Games', the new series from Yahoo Sport Australia exploring the often brutal mental toil elite athletes go through in pursuit of greatness:
Click here to sign up to our newsletter for all the latest and breaking stories from Australia and around the world.