Rafael Nadal puzzled by timing of Andy Murray's US Open withdrawal

Rafael Nadal says he could not understand the timing of Andy Murray's withdrawal from the US Open.

The world No. 2 had come to New York, having been sidelined with a hip injury since Wimbledon, but withdrew the day after the draw came out. If Murray had withdrawn before the draw was made, third seed Roger Federer would have been moved into his spot, on the other half from Nadal.

Nadal saw Murray on the grounds before the tournament began.

"But I always thought that he gonna be playing if he was here practicing," said Nadal. "Was a little bit strange that he retired just the morning after the draw was made."

The Spaniard added that he hoped Murray would have a "fast and good recovery," but could not tell why Murray had not held off until the start of play to give himself the most time to recover, or withdrawn beforehand if it was obvious he could not play.

"Normally you want to keep practicing, keep trying, until the last moment. You don't retire Saturday morning," said Nadal. " You retire Monday morning or Sunday afternoon, not Saturday morning. If not, you can do it before the draw. That's why I say it's strange.

"But of course he has his reason, and for sure the negative—the only news, and the negative news, was that he will not be playing here."

The world No. 1 won his first round in straight sets, taking a tight first set, but says he has been playing at a higher level in practice.

"I feel that I am practicing much better than what I did in Montreal and Cincinnati. That doesn't mean that you're gonna have a great result, but the real thing, the feeling is much more positive," he said. "So I am confident I am ready to play much better than what I did today."

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