Rafael Nadal forced to retire from US Open semi-final with injury as Juan Martin del Potro reaches final

The world No 1 was 7-6, 6-2 down against Del Potro when he withdrew from the tournament after suffering a recurrence of the tendinitis that plagued him earlier in the year

The physical pain was all too familiar but for Rafael Nadal it was the emotional anguish that hurt the most as the world No 1 was forced to retire from the latter stages of a Grand Slam tournament for the second time in the last eight months here on Friday.

Juan Martin del Potro was leading 7-6, 6-2 in their US Open semi-final when Nadal quit because of the latest problem with his perennially troublesome knees. Having felt a recurrence of tendinitis in his right knee early in the first set, Nadal soldiered on until the end of the second before quitting.

“I hate to retire, but to stay one more set out there playing like this would have been too much for me,” Nadal said afterwards. “As you could imagine it was very difficult for me to say goodbye before the match finished, but at some point you have to take a decision.

“It was so difficult for me to keep playing at the same time that way, having too much pain. That wasn’t a tennis match at the end. It was just one player playing, the other one [not moving] on the other side of the court.”

Nadal had played through a problem with the knee earlier in the tournament but in the fifth game of the opening set of the semi-final he felt it again. He said the pain was all too familiar, though it was usually worse when it came on suddenly, as it did on this occasion, rather than over a matter of time.

This has been an especially demanding tournament for Nadal. He had been on court for a total of nearly 16 hours in his first five matches – often in gruelling heat and humidity – and had featured in three exceptionally hard matches, against Karen Khachanov, Nikoloz Basilashvili and Dominic Thiem. His quarter-final victory over Thiem finished at 2am after four hours and 49 minutes.

However, Nadal said he was not sure whether those exertions had had any effect on his knee and stressed that he had not had a problem in practice since his last match.

Nadal could not predict how long it might take him to recover from the injury. “This is not an injury like when you break something,” he said. “This is tendinitis. You just have to make a decision as to whether you want to wait till you feel almost nothing or you want to keep going with pain.”

Rafael Nadal tried to battle on through the pain but was unable to see the match out (EPA)

Nadal is next due to play at the China Open in the first week of October, but there must be a possibility that he will not compete again this year, although that could damage his hopes of finishing 2018 as the year-end world No 1.

He has already qualified for the Nitto ATP Finals at the O2 Arena in London in November, though he has not played in the season-ending event on five previous occasions after qualifying and pulled out last year after only one match.

This was the fourth time in his career that Nadal has failed to finish a Grand Slam tournament. He quit with a knee problem in the third set of his 2010 Australian Open quarter-final against Andy Murray, pulled out of the 2016 French Open before the third round because of a wrist injury and retired in the fifth set against Marin Cilic in this year’s Australian Open quarter-finals after damaging a hip muscle.

The rest of the year now appears to be in doubt for Nadal (Getty)

The Spaniard has also pulled out of tournaments this year at Acapulco, Indian Wells, Miami, Queen’s Club and Cincinnati because of physical issues, which makes his position at the top of the world rankings all the more remarkable.

Nadal said he had had “a fantastic year” until now, pointing out that he had lost only four matches, two of them retirements at the business end of Grand Slam tournaments.

“That’s frustrating and tough for me,” the Spaniard said at his post-match press conference. “It’s not about losing. It’s about not having the chance to fight. I feel that I have fought all my career against these kind of things, too. I missed a lot of opportunities. But on the other hand, I have also won a lot.

Juan Martin del Potro moved into the US Open final as a result (AFP/Getty)

“These moments are tough, but at the same time I will keep going and keep working hard to keep having opportunities. I know things are going the right way. I am playing well. I am enjoying being on court. I am having a lot of success. I am very competitive at the age of 32.

“A lot of people in this room, including myself, never thought that at the age of 32 I would still be here fighting for titles, fighting to lead the world rankings.

“All my career everybody has said that because of my style, I would have a short career, but I am still here. I’m still here because I love what I am doing. I still have the passion for the game. I’m going to keep fighting and working hard to keep enjoying this tour and keep having chances to compete at the highest level.”

Nadal suffered a recurrence of the tendinitis that hampered him earlier in the year (AP)

When a reporter pointed out that Roger Federer and Novak Djokovic had also had injury issues in the last two years, Nadal insisted that there was no comparison between his situation and that of his two biggest rivals. He said that their careers had not been affected by injuries in the same way that his had.

Since 2003 Nadal has missed eight Grand Slam tournaments through injury and retired during another four because of physical issues. Federer, meanwhile, played 65 Grand Slam tournaments in succession until he missed the 2016 French Open through injury, while Djokovic had played 51 in a row until he missed last year’s US Open because of an elbow problem.

Nadal was asked what he thought about Del Potro’s return to a Grand Slam final after so many years of struggle with injuries.

Nadal was forced to retire injured from his US Open semi-final against Del Potro (Getty)

“I can't say that I am happy because I am not,” Nadal said. “But, yes, he's a player who went through lot of issues during his career, like me. I know how tough this is. I know how much frustration you feel when you can't do the things that you want to do. He knows that very well too.

“I’m happy for him that he's able to be back at his top level. I wish him all the best. For him it will be huge if he's able to win a Grand Slam again.”