Rafael Nadal, whose record streak on clay was stopped by Roger Federer last weekend, believes the world number one will beat him again on the slow surface and just hopes it will not happen in the French Open final.

Spain's Nadal, who had gone 81 matches without defeat on clay until he fell to Swiss Federer in the Hamburg final last Sunday, is going for his third successive crown at the French Open starting on Sunday.

"Roger played better than me and he beat me," said Nadal, who will be keen to maintain his 100 percent record at Roland Garros.

"Some day it's going to happen again because he's an unbelievable player on every surface and he can beat me on clay, for sure."

Federer, who had never beaten Nadal on clay before Hamburg, fell to the muscular Spaniard in the final here last year and in the semi-finals the year before.

"Roger's confidence is going to be good because he won in Hamburg but mine is good too because I won Monte Carlo, Barcelona and Rome and reached the final in Hamburg," Nadal said on Friday.

The world number two was philosophical about having lost after remaining undefeated on his favourite surface for more than two years.

"I'm not happy to have lost in Hamburg but the record is there, 81 victories. That's unbelievable. It's going to be very difficult to improve."

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