A gracious Roger Federer [Images] took his hat off to Spanish birthday boy Rafael Nadal [Images] on Friday after losing to the 19-year-old in the French Open semi-finals.

"He deserved his victory... he was the better player tonight," the Swiss world number one said after his 6-3, 4-6, 6-4, 6-3 defeat.

"Never take anything away from somebody who beat me, because I was trying my best."

The match finished in twilight after rain had delayed the start of the day's play and Mariano Puerta took five long sets to beat Nikolay Davydenko in the first semi-final.

Federer said he had wanted to call off play as night fell and finish the match on Saturday.

"I could hardly see the ball in the end," he said. "I am disappointed we continued.

"I don't want to say it was a coin toss or anything in the end, you know. I played poorly to finish off the match... he was just consistent and solid.

"I wished we could have continued tomorrow. But I guess it's too late now."

The Swiss said he had never really got going in the match.

"Simple version for me is it started bad and finished bad," he smiled. "Was good in the middle and that was not good enough. That's like the short and simple version.

"It was the start, basically trying to get used to his lefty spin. Kind of always takes me a while to figure out.

"It's not good to lose a set until you figure it out.

"All in all I'm not so happy with my performance, to be honest.

"I really thought I had the keys to beat him today and it was just unfortunate that I wasn't at my best.

"I think that my tactics were okay but I should have played a bit better, and that's exactly what I wasn't able to do."

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