Rafael Nadal quits US Open semi-final sending Juan Martin del Potro through

US Open
Rafael Nadal angry

Juan Martin del Potro is through to the US Open final after Rafael Nadal retired hurt in their semi-final.

The world number one was struggling throughout, and opted to withdraw with a knee injury after Del Potro took a two set lad.

The first set was a very tight affair with Nadal probing the Del Potro backhand, and the pair traded breaks before the Argentinian finally sealed it with a tiebreak.

However, Nadal’s lack of mobility started to really show in the second set.

The defending champion has battled through some long matches in the tournament so far, with a near five-hour epic against Dominic Thiem in the quarter-finals possibly the final straw for his knee.

And, after dropping the second set 6-2, Nadal withdrew allowing Del Potro to take his place in the final of the tournament he won in 2009.

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