Washington - London Olympic finalist Roger Federer joined Rafael Nadal in withdrawing from the ATP Toronto Masters, with Canadian officials releasing the news shortly after the Swiss reached the gold medal match at Wimbledon on Friday.
Nadal, ranked third, withdrew on Thursday as he continues to try to heal the knee tendinitis which has wrecked his summer.
Seven-time Wimbledon winner Federer said in a statement that he would not be crossing the Atlantic for the tournament start on Monday.
"I'm very disappointed that I have to withdraw from Toronto," said Federer, winner of a marathon semi-final at the Games over Argentine Juan Martin del Potro which ended 19-17 in his favour in the third set on Friday.
"After a long stretch of tournaments, I will need some time to recover," said the Swiss star.
"I look forward to coming back to Canada next year."
The Olympic final against Andy Murray will be the best of five sets on Sunday.
Federer turns 31 on Wednesday and would have likely played his opening match on his birthday at a tournament which has given all 16 seeds byes into the second round.
Nevertheless, the withdrawal list is growing. Also out are Nadal's Spanish compatriots David Ferrer and Fernando Verdasco plus Frenchman Gael Monfils (knee injury).
American Andy Roddick pulled out with a shoulder problem.