PARIS — Fresh off a ragged, rugged, five-set French Open semifinal victory yesterday, Roger Federer was leaving for the night when a dozen or so fans drew his attention.

They wanted photos and autographs, and Federer obliged, signing hats, a poster, even one guy's white polo shirt. As Federer ambled off, a man shouted: "Win on Sunday! Please!"

Pausing for a moment before sliding into a car, Federer turned and, with a quick wave of his skilled right arm, replied, "OK." Ah, if only it were that simple. For all his accomplishments, for all his trophies and records, Federer now wants — needs? — to do something he never has: win a final at Roland Garros.

By coming back to beat No. 5-seeded Juan Martin del Potro of Argentina, 3-6, 7-6 (2), 2-6, 6-1, 6-4, Federer moved within one victory of his first French Open championship.

Federer will face No. 23 Robin Soderling of Sweden for the title. Soderling reeled off the last five games of a 6-3, 7-5, 5-7, 4-6, 6-4 victory over No. 12 Fernando Gonzalez of Chile in yesterday's first semifinal

If he can beat Soderling tomorrow, Federer also will tie Pete Sampras' career mark of 14 Grand Slam singles titles. And he will become only the sixth man with a career Grand Slam, at least one title from each of tennis' four majors.

"There's still one more step," Federer said.

He's come exactly this close in the past, losing each of the last three French Open finals to Rafael Nadal, along with a semifinal four years ago. But this time, Nadal is not around to torment him, having been stunned by Soderling in the fourth round.

"Obviously," Federer said, "it's nice to see someone else for a change."

Since the start of the 2005 French Open, Federer is 0-4 against Nadal at Roland Garros, 29-0 against everyone else. Similarly, over the course of his career, Federer is 2-5 against Nadal in Grand Slam finals, 11-0 against all other opponents.

Federer just so happens to have a 9-0 career record against Soderling will be playing in his first Grand Slam final. He'd never been past the third round in 21 previous majors.

Does Soderling believe he has a chance against Federer?

"He's going to be the favorite, by far," the big-serving Soderling said. "But I think Nadal was the favorite against me as well."

Soderling's first Grand Slam championship match will be Federer's 19th, matching Ivan Lendl's record, and the Swiss star's 15th in the last 16 major tournaments.

Early on against Federer, the 6-foot-6 del Potro used his long legs to speed around the court and his long arms to whip winners.

"He came out of the blocks really strong," Federer said.

Federer did not, even slapping himself in the face after one poorly executed point. Five miscues by a suddenly tight del Potro in the tiebreaker ceded the second set, and it took Federer 2 1/2 hours to convert a break point.

When he did, it put Federer ahead 3-1 in the fourth set and really got him going. He broke del Potro twice more to level things at two sets apiece.

After double-faulting to hand Federer a 4-3 lead, del Potro trudged to the sideline with head bowed.

Three games later, Federer served it out.

Against Soderling, Gonzalez went up 4-1 in the fifth set, and would say: "I really thought I was going to win."

Turned out he wouldn't win another game.

"Didn't look good," Soderling said. "I just tried harder, and all of a sudden, it all worked again."