Rafael Nadal’s greatest opponent hasn’t been Roger Federer in recent years, but it's actually been his right knee.
It has kept him out of over 10 major tournaments over the course of his career, alongside other injuries.
The legendary Spaniard has been forced to miss another, after withdrawing from the Paris Masters earlier today.
It’s the same old injury, and the same old Rafa gritting his teeth, and trying to play through it.
He reached the quarter finals where he was due to play Filip Krajonovic, the Serbian, but he today confirmed in a press conference that his tournament was coming to an early end.
“I have to pull out,” Sky Sports reported.
"Of course, it's a very tough decision for me, especially here in Paris, which has been the most important city in my career without a doubt.
"It's a tough situation but I tried my best. I did one treatment yesterday night to try and play today. I am here to win so if I see that I don't have that chance, it's not a good idea to keep trying.
"It's not about London, it's about the longer term. It is important to play tennis as long as possible.
Nadal fought hard to reach the quarter finals with a gruelling tie against the Uruguayan Pablo Cuevas. It was an occasion which saw Nadal take to the field strapped up and struggling to generate power through his leg.
But, Nadal decided not to risk his knee any further with a view to “play tennis as long as possible.”
With injuries wreaking havoc to him in the past, allowing players like Andy Murray and Novak Djokovic to emerge, Nadal has taken a longer term approach.
“I’m going to do my treatment,” he told reporters. “In the past it worked well.”
Such news makes him a doubt for the ATP finals beginning on November 12. He was hoping to add another major tournament win to the two Grand Slams he’s already won this year.
However, it isn’t all bad news for Nadal.
His recent record means that he is guaranteed to end the year as the world number one.
For a competitor such as Nadal, the withdrawal must have grated, especially as it was in Paris which he described as “the most important city in my career.”
All most tennis fans can do is hope that it isn’t as serious as the tendonitis he has suffered in the past, and that both he and Roger Federer can continue with the glorious swansong of their careers.
Nadal is the best in the world, but for a player with a work ethic as formidable as his own, injuries can often hit harder than they would for other players.