Chink in Fed's armour gives Davydenko hope

Fourth seed Davydenko may have lost all of his previous eight meetings with the greatest player in the game, but this tournament is the only Grand Slam title the Swiss has yet to win and the surface exposes weaknesses not seen on grass or hard courts.

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And, despite his domination of the men's game, Federer showed yesterday that even he isn't perfect as he played a terrible second set during a 7-5, 1-6, 6-1, 6-2 quarter-final victory over Spain's Tommy Robredo.

Federer even admitted he had got his tactics wrong, which is something he hardly ever has to reveal.

He said: "I was actually playing wrong at that point of time and I was struggling, that's true. I was very happy with the way I reacted and I started to mix it up better."

Despite that winning run against Davydenko, Federer recognises the Russian is a real threat on clay and will not let the fact tomorrow's match will see him extended his own record to 12 successive Grand Slam semi-final appearances allow complacency to creep in.

He said: "If I can break some records - like 12 semi-finals - that's fantastic, but I don't want to think about records, especially here at Roland Garros. If you lose, it's a little bit disastrous."

"Nikolay has a strong mindset and I think that he can play on all surfaces. On clay, he's going to be a tough opponent but I have never lost against him.

"I played against him in Milan a few years ago and while he was a good player, he wasn't fantastic. He had some shortcomings in his game but now he is much more consistent from the baseline and his serve has improved a lot.

"He's always been a great runner from the baseline, very tough to play against."

Federer will be happy Davydenko made it into a repeat of their 2006 US Open semi-final.

Had the Russian lost his quarter-final, the world No1 would have been facing Guillermo Canas, who has beaten Federer twice on clay this year and would have been confident of recording a remarkable hat-trick.

Davydenko, whose gaunt appearance put off potential clothing sponsors until the French company Airness signed him up this year, has been trying to minimise his time out court and a 7-5, 6-4, 6-4 win over Argentine Canas was a help.

Davydenko said: "I need to win in three sets every match. I can't play five sets always. It's, like, look at me, I'm already 70 kilos. How many kilos am I losing after five-set matches? I can be 40 kilos then!"

Having lost to Federer in the Flushing Meadows semi-final, Davydenko knows the enormity of the test he faces.

"In the US Open, I just tried to do my best and I didn't play so well. He just hit me in three easy sets, and I had no chance.

"I was disappointed but now I am feeling great, and I'm coming to fight and to try to win. You need to find a game to play against Federer, That's what I need, Against me, he has never lost and he has more confidence."

To keep his hopes of a third successive men's title alive, Nadal has to defeat his fellow Majorcan Carlos Moya, the 23rd seed in today's quarter-final.

Moya, the 1998 champion, is capable of causing his great friend major problems but the odds favour another win for the youngster.

If Nadal makes it into the semi-finals, he will face either sixth seed Novak Djokovic or Russian Igor Andreev.

Djokovic has already seen two Serbian women reach the last four of their tournament, although Andreev, who has already beaten Andy Roddick and Marcos Bagdhatis in Paris this year, is capable of causing another upset.

Djokovic, who is one of British No1 Andy Murray's best friends on tour, believes there is much more to come in his game.

The Serb, beaten at this stage by Nadal last year, said: "There is always room for improvement and I think that's a positive thing. Even Roger Federer, who is a perfect player in everybody's eyes, still thinks that there is improvement to be made. Nobody can be perfect and you always make mistakes.

"Last year, I honestly didn't expect to be in the quarter-finals. I was not the favourite and against Nadal I was physically exhausted. I retired because of my back problem and in my mind, I was pretty much satisfied with my achievements in getting to the last eight. This year is much different, and I am one of the favorites."

Andreev is the only unseeded player left in the draw, but is only way down the rankings - at number 125 - because of a knee injury that sidelined him for most of last season.

The 23-year-old was the last person to beat Nadal on clay, in April 2005, before Roger Federer defeated the Spaniard in Hamburg last month.