He's one of the most competitive sportsman on the globe, but world number one Rafael Nadal may need to change the ways he trains to continue competing in grand slams.
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Nadal was forced to retire last night in the fifth set of his quarter final clash against Marin Cilic after he was hampered by an injury to his upper right leg.
Nadal, now 31, has been impacted by long-term injuries previously, but he has only retired once in a grand slam before some eight years ago against Andy Murray at the same tournament.
That's why Australian tennis coach Roger Rasheed thinks it was hard for Nadal to let go of an opportunity to win another grand slam.
"It was unfortunate with Rafa, with this injury and for him to pull out, he's a guy who's arguably in the top two or three competitive sports people ever in sport globally,'' Rasheed told Big Sports Breakfast.
"When he pulls out, you know he can't obviously see the finish line before him."
Rasheed believes as Nadal gets older, he may need to reduce his heavy workload at training.
"The wear and tear is the training, maybe you need to dial that down completely and see where that takes you for your career,'' he said.
"Once you're getting deep into your career, injuries do front up, it's just general wear and tear of the human body.
"Rafa trains at an absolute premium, what you see on a match court, you just multiply that by the amount of time he's actually hitting the ball [in training]."
The Australian tennis coach has also suggested following in the footsteps of his closest rival, Roger Federer, who reduced his training workload to prolong his career.
"I think Roger's done an excellent job of that,'' he said
"It's an interesting discussion that will always be there when you've got a few guys getting injured in their later years of tennis."
Nadal let fly at ATP officials after his retirement last night, suggesting improvements to scheduling need to be made to focus more so on player welfare.
"Somebody who is running the tour should think a little bit about what's going on," said Nadal in his post-match news conference.
"[There are] too many people getting injured, I don't know if they have to think a little bit about the health of the players.
"Not for now that we are playing, but there is life after tennis. I don't know, if we keep playing on these very, very hard surfaces, what's going to happen in the future with our lives."
