Rafael Nadal has withdrawn from the US Tennis Open to focus on his battle with tendinitis in his knee.
The Spanish world number three played his last match at the end of June, losing in the second round at Wimbledon to the Czech Lukas Rosol, and he had been dropping hints for weeks that his condition might not be improving.
Nadal won the US Open in 2009 and lost to Novak Djokovic in the final last year.
The final major championship of the year starts on Monday week.
