© Sarah Stier/Getty Images

Rafael Nadal departs Arthur Ashe Stadium after retiring from his US Open semi-final against Juan Martin del Potro.

Nadal: "It Was So Difficult For Me To Keep Playing"

World No. 1 reflects on his decision to retire from his US Open semi-final

Rafael Nadal knew it was time.

For one of the greatest, most dogged gladiators in ATP history, this was one of the hardest decisions the World No. 1 has had to make. Trailing by two sets to love in his US Open semi-final against Juan Martin del Potro, Nadal was forced to stop play due to knee tendinitis.

It was the cumulative effect of a long and arduous fortnight that saw the Spaniard not only battle through the two longest matches in his US Open career, but also the oppressive heat and humidity that has plagued Flushing Meadows. And with Del Potro's powerful game in full flow at 7-6(3), 6-2, Nadal says he had no choice but to retire from the match.

"I hate to retire, but to stay one more set out there playing like this was too much for me," Nadal told the assembled media following the match. "I had some issues during the tournament. Today at 2-all in the first I felt it again. I said to my box immediately that I felt something in the knee. After that, I was just trying to see if it could improve during the match. But no, it was not the day.

"I waited as much as I can. You could imagine it was very difficult for me to say goodbye before the match finish. But at some point you have to make a decision. It was so difficult for me to keep playing that way, having so much pain. It was not a tennis match at the end. It was just one player playing, the other one staying on the other side."

World-class agility has been a staple of Nadal's game throughout his career, but he admits that the tendinitis significantly hampered his movement on Friday. The Mallorca native was unable to exhibit his signature defence and track down the thunderous blows coming off Del Potro's racquet.

It marks the second time this year in which Nadal has retired from a Grand Slam match, having stopped play in his Australian Open quarter-final against Marin Cilic with a right leg injury.

You May Also Like: Delpo Advances To Second US Open Final

"I cannot compare the knee with the other times because the pain is always very similar when I have it," Nadal added. "The problem is this time it was something a little more aggressive because [I felt it] in one movement. It was not something progressive. So I don't know what can happen in a couple of days or in a couple of weeks.

"It is tough, these moments, but at the same time I am going to keep working hard to have these opportunities. I know the things are going the right way. I am playing well. I am enjoying on court. I am having a lot of success. I am very competitive at the age of 32. I am here fighting for titles, fighting for the first position of the ATP Rankings.

"Last year was a fantastic year. This year has been a fantastic year until this moment. I lost four matches. Two of them I had to retire. The negative thing is that those two were in the quarter-finals and semi-finals of a Grand Slam. That's frustrating."

Despite the premature exit, Nadal was full of praise for Del Potro, who advances to his second US Open final. Nine years ago, the Argentine also defeated the Spaniard in the semi-finals, en route to his lone Grand Slam crown.

"He's a player that went through a lot of issues during his career, like me too. I know how tough it is. I know how much frustration can be when you can't do the thing that you want to do. He knows that very well.

"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."

More stories like this in: