World number one Roger Federer [Images] said on Sunday the defeat by Rafael Nadal that denied him a sixth successive Wimbledon title was the hardest of his career and was partly caused by bad light.

- Images from the final

The Swiss said he was not looking for excuses but pointed to fading light on Centre Court as a hindrance in the thrilling 6-4, 6-4, 6-7, 6-7, 9-7 final, which was twice interrupted by rain.

"It is a disaster, the French is nothing in comparison," a subdued Federer told a news conference. Federer has lost to Nadal three times in the French Open final.

"It's rough on me now, obviously, you know, to lose the biggest tournament in the world over maybe a bit of light," the 26-year-old told a news conference.

"It's not a whole lot of fun, but it's the way it is. I can only congratulate Rafa for a great effort."

Federer, who said he had also struggled because of the gusty conditions, had been chasing a modern-era record of six All England [Images] Club titles in a row and his disappointment was immense.

"(It was) probably my hardest loss, by far. I mean, it's not much harder than this right now," he said.

Federer said it was too early for him to appreciate what a fantastic contest he had been part of.

"Probably later on in life, you know, I'll go, 'That was a great match'. But right now it's not much of ... a positive thing to end this match," he said.

"I'm happy we lived up to the expectations, you know. I'm happy the way I fought. That's all I could really do."

He said he had been pleased with the many astonishing shots he had managed to pull out of the bag at critical moments and that he had been sure that by forcing the match into a fifth set the momentum would have been with him to go on and win.

"Really, I just think we both played tough till the very end, you know. In tennis, unfortunately sometimes there has to be winners and losers. There's no draws."

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