MIAMI — The French Open starts on a different note this year — with Roger Federer as the defending men's champion instead of Rafael Nadal, who won four in a row from 2005 to '08 and is 31-1 overall on the clay at Roland Garros.

Although it wasn't the Spaniard whom Federer beat in the final last year, winning his first French Open was emotional, and he would love nothing more than to successfully defend his title. If he can beat Nadal in the final, even sweeter.

Federer admitted after the draw Friday that "it felt different" walking into the grounds, with memories of holding up the trophy. He also said he feels more relaxed than usual.

"I feel a little less pressure because I've proven it to myself — and maybe to many other people," he said.

The pressure is more on Nadal, who enters the tournament as the heavy favorite. He is 31-4 this year, including 15-0 on clay, and is coming off a trio of clay titles at Monte Carlo, Rome and Madrid.

Nadal's history at Roland Garros is mind-boggling. He beat Federer in the 2005 semifinals and in the final in 2006, '07 and '08.

He struggled with tendinitis in his knees last year, but the second-ranked Nadal looks like he's back to his old ways.

Federer, meanwhile, is 6-3 on clay this season. And he lost to Nadal in straight sets in the final at Madrid last weekend.

"I'm not going to go on a limb," John McEnroe said. "Nadal is the overwhelming favorite, and I would pick Federer as next."

McEnroe's brother, Patrick, also a TV commentator, agreed

"I expect Nadal to mow down the field in Paris," Patrick said. "No doubt, he is the heavy favorite. He has that look in his eye, especially on clay.

"It seems the pretenders are gone, and it's back to the Roger and Rafa show. Those two guys remain the two to watch, and everyone roots for them to make a dream final."

The women's side is more unpredictable.

Will four-time winner Justine Henin pick up where she left off in 2007? The French Open is her favorite tournament. In fact, one reason her abrupt retirement was so shocking is that it came on the eve of the 2008 French Open. No woman has had more success there in recent years, and the only question is whether she is ready to win a major title again. She reached the final at the Australian Open but has been up and down since.

Serena and Venus Williams are ranked first and second, respectively, in the world for the first time since 2003, and both have a chance to win. Serena won the French in 2002 but was beaten in the third round in 2008 and the quarterfinals last year. A knee injury kept her off the court from February through April, and she hasn't played in a singles final since winning the Australian Open.

Venus made it to the final at Madrid last week, but lost to unheralded Aranane Rezai. Venus has never won the French Open, losing in the third round the past three years.

"I don't know the status of Henin, but she is the favorite; she's had the most success there," John McEnroe said. "The Williams sisters are the X-factor. They're capable of winning, but sometimes they lose their way on clay. It's more of crap shot after those."

Martina Navratilova, who is doing commentary for the Tennis Channel, agreed that Henin is the women's favorite despite her layoff.

"Even though Justine has been away for a couple of years from the French, she has played enough matches now this year and has proven herself where she has to be one of the favorites for the title, no doubt about that," she said. "Nobody has really come through in a dominating fashion of leading up to the tournament. So, she must like her chances pretty well on this stuff."

That said, Henin has a tough draw. She could face Maria Sharapova in the third round and Serena in the quarterfinals.

Navratilova said she has been impressed with Venus Williams' rise to No. 2 in recent months but said Venus must be more aggressive on clay to win her first French Open.

"She is definitely playing better ball, as the ranking indicates," Navratilova said. "Movement-wise, I think she moves better on the clay than her sister, Serena. The results haven't been as good. I think she seems to play too passively on the clay. I always said she needs to pretend she is on grass and position herself more similar to how she plays on grass."

Oh, yes. And then there's defending champion Svetlana Kuznetsova. She often gets forgotten in the conversation, but she won in 2009, made the semifinals in 2008 and the quarterfinals in 2007. She is off to a rocky start this clay season but always is dangerous when she gets to Roland Garros.