PARIS - Twice Roger Federer took an awkward spill yesterday, leaving the regal champion sprawled on the clay that has tripped him up before.

The French Open can be humbling, as Federer well knows, but he'll try again for his first Roland Garros title tomorrow against nemesis Rafael Nadal.

The top-ranked Federer endured some messy moments in the semifinal. Knocked down but not out, he wiped off the dirt and defeated unseeded Frenchman Gael Monfils, 6-2, 5-7, 6-3, 7-5.

Nadal's earlier semifinal was close only by his standards: He lost 12 games and nearly lost a set. The king of clay beat No. 3-seeded Novak Djokovic, 6-4, 6-2, 7-6 (3).

Nadal had lost only three games in each of his previous two matches. He's one win from becoming the first player since Bjorn Borg in 1981 to win four consecutive French Open titles, while Federer seeks the only Grand Slam title he has yet to win.

"Against Federer is special," Nadal said. "I will try and face history."

Nadal has beaten Federer at Roland Garros the last three years.

"It will be fun to play him again," Federer said. "I will try everything. I hope I will finally win here."

Ana Ivanovic and Dinara Safina will bid for their first Grand Slam title today in the women's final.

For a brief time, the Nadal-Federer rematch appeared in jeopardy. Federer struggled against Monfils, especially in the final game of the second set, when he looked nervous serving and shanked a forehand on the final shot.

The partisan crowd roared, sensing a possible upset.

"I thought that would put pressure on Roger, but he didn't feel any pressure," Monfils said. "The crowd was behind me all the time. But then I was playing Roger, and French people love him as well."

Federer regained his composure and endured some brilliant play by the streaky Monfils down the stretch.

"He was magnificent," Federer said. "He was always trailing, but he hung tough, he fought back. It almost paid off. At the end, anything could have happened. So I'm very relieved."

Scrambling rallies twice sent Federer tumbling, while Monfils fell at least four times. Playing aggressively, Federer reached the net on 64 points - a lot on clay - and won 49.