Roger Federer believes the pressure will all be on Novak Djokovic when the pair meet in the French Open semifinals on Friday.

Victory for Djokovic, the second seed, will see him replace Rafael Nadal as world number one, while he would also equal John McEnroe's 1984 record of 42 matches unbeaten at the start of a season.

With so much on the line, Federer says he can afford to approach the encounter in a more relaxed frame of find than his adversary.

"There's less at stake for me than for him," said Federer, the 2009 champion.

"He's got a lot of things going on. I'd love to be in a Grand Slam final, because I haven't achieved it for a few Slams, but it's nothing major for me, as long as I keep playing well."

The burgeoning rivalry between Nadal and Djokovic, who has beaten the Spaniard in three Masters finals this year, has cast Federer into the unfamiliar role of support act.

The great Swiss is seeded outside the top two at Roland Garros for the first Grand Slam since Wimbledon in 2003, while he is also without a title at a major since the 2010 Australian Open.

Despite his crown having slipped, however, the 29-year-old 16-time Grand Slam-winner says he is not desperate to keep Djokovic from the number one position.

"It's not the driving force behind this match, to be honest," he said, after beating French ninth seed Gael Monfils 6-4, 6-3, 7-6 (7/3) in the last eight.

"For me the plan is trying to get a step further and into the final at the French Open. That's the big picture, that's what I entered for.”

"It wasn't to stop Novak."

Djokovic has assembled a 43-match winning streak since the end of 2010 and Federer said the 24-year-old world number two was coping admirably with the strain of putting together such a run.

"He's keeping it up and he's not making a big fuss about it, which is good for him," said Federer.

"It's hard being asked the question - 'How many wins can you get?' - day in, day out. I'm sure it's been tricky for him but he's been doing a great job.”

"The number one is the big one for him now through, rather than the streak. So it's going to be an interesting one."

Federer possesses a 13-9 win-loss record against Djokovic but has tasted defeat in their last three encounters, including a straight sets loss in the semifinals of this year's Australian Open.

They have not met on clay since Djokovic prevailed in the semifinals of the 2009 Rome Masters, however, and Federer admitted he would have to remind himself what it was like to tackle his Serbian rival on a claycourt.

"We played quite a bit in a six-month period up to Indian Wells, maybe six or seven times," said the Swiss.

"This is obviously different, being on clay... We'll have to see what the conditions are like on the day."

He added: "Against each other we tend to play positively and not give each other time. He's been playing fantastic this season and I know I'll have to play my best tennis.”

"I don't think you have to change a lot (to adapt to the surface), but I haven't played him on clay for a long time."

Djokovic, who beat Argentine 25th seed Juan Martin del Potro in round three and French number 13 seed Richard Gasquet in round four, was given a walkover in the quarterfinals after Italy's Fabio Fognini withdrew with a thigh strain.

"Walkover from Fognini. Bad luck for him, hope he recovers fast. Today I get to enjoy Paris in a different way," Djokovic wrote on his Twitter account after Fognini pulled out of their match on Monday.

The Serbian star, who claimed his second Grand Slam title at the Australian Open and has seven tournament wins to his name in 2011, has never gone beyond the last four at the French Open.