Roger Federer and Rafael Nadal have not put a foot wrong so far at this year's French Open and all signs point to the world's two outstanding men's players duelling for the title on Sunday.

There are still some pitfalls lurking on the Parisian clay, however, and Tuesday and Wednesday's quarter-finals will be a better yardstick of their form after they both arrived at the business end of the tournament with a 12-0 sets record.

On Tuesday Federer faces Robin Soderling, the man he beat in last year's final to complete a career Grand Slam after the Swede cleared the decks with a sensational defeat of Nadal.

Four-times champion Nadal, hungry to prove that last year's fourth-round shocker against Soderling was an aberration, will have to pass fellow Spaniard Nicolas Almagro, a player whose five career titles have all been on clay.

Since beating Nadal last year Soderling has transformed into a genuine top-10 player and his form here has been only marginally less impressive than Federer's.

He has never beaten the Swiss master in 12 attempts though and Federer oozed confidence when he looked ahead to another clash with the powerhouse Swede.

"He's going to be fitter than in the past when I played him during the third round or second round," Federer said.

"But I'm really looking forward to this match because he hits very strongly, forehand, backhand and serves. This is what I like. This is why I have a good record against him."

Soderling knows the odds are against him but his body language now suggests a player who believes he can beat anybody when his game clicks into place.

"Even against Roger you will always get a few chances," he said. "Then you have to take them, because he won't give you any second opportunities. You have to play well in the important points, which he does so well, that's why he's so good."

After a patchy start against French teenage wildcard Gianni Mina, Nadal's game has gone up several levels and he appeared to be peaking at the right moment but is still not taking the threat posed by Almagro lightly.

"It's going to be complicated, he's going to be very aggressive, but I'll do my best to make him feel uncomfortable," Nadal said after beating Brazil's Thomaz Bellucci in straight sets on Monday.

The other men's quarter-final in the top half features Czech Tomas Berdych against Russian Mikhail Youzhny, both enjoying their best runs at Roland Garros.

Should Nadal overcome Almagro he will be up against either world number three and regular sparring partner Novak Djokovic or Grand Slam quarter-final debutant Jurgen Melzer - the first Austrian to reach the last eight at Roland Garros since 1998.