Former world number one Yevgeny Kafelnikov has speculated that Rafael Nadal could decide to retire from tennis if he wins the French Open on Sunday.
Nadal is just two wins away from a 14th French Open title at 22nd career major - a total no one else in the history of male tennis can currently touch.
He beat his old foe Novak Djokovic in the quarter-finals on Tuesday in what was one of the most high-quality match-ups in history.
However, Nadal has warned he is unable to guarantee this will not be his last tournament at Roland Garros due to a chronic foot injury that kept him out for a large chunk of last season.
"I'm very clear about it," Nadal said, "being old enough not to hide things or come here and say something I don't think so.
"I don't know what can happen after Roland Garros; as i said before i will play this tournament because we are doing things to be ready to play it but I don't know what will happen next.
"I have what I have there in my foot, so if I can't find an improvement or a little solution, it will become super hard for me.
"I'm just enjoying every day that I have a chance to be here, not thinking much about what's going to happen next.
"Obviously we will struggle to find a solution but, for the moment, I have none. So just having the chance to play another semi-final here at Roland Garros gives me a lot of energy."
He will play Alexander Zverev in the semi-finals on Friday and, while Kefelnikov doesn't give the German any chance of beating Nadal, he does think an imminent retirement is possible.
"Maybe this is the last time Djokovic and Nadal will play against each other," Kafelnikov said.
"Maybe Rafa will say on Sunday that he will retire after the 22nd Grand Slam title.
"Maybe he will say: 'It's over, see you in the next life'. I hope he continues, but you never know.
"As much as I love Alexander Zverev, I don't think he has any chance against Nadal. The only one who can annoy Rafa, believe it or not, is Casper Ruud.
"I think he has the necessary style of play and he can play a long game. Now Rafa is the absolute favourite."