By Julien Pretot NEW YORK, Sept 7 (REUTERS) Roger Federer blamed troubled preparations for his US Open quarter-final exit on Wednesday, saying he had spent most of the time leading up to the year's final grand slam worrying about his back instead of focusing on training.
The 36-year-old Swiss, who was chasing a 20th major title and was hoping to play world number one Rafa Nadal for the first time in Flushing Meadows in the last four, lost 7-5 3-6 7-6(8) 6-4 in a thrilling encounter on Arthur Ashe Stadium.