By Martyn Herman
(Reuters) - Six different champions in the last six years suggests that tipping a French Open women's champion is something of a lottery, but those backing world No.1 Serena Williams are surely investing wisely.
The American powerhouse claimed a second Roland Garros crown last year - 11 years after her first - and warmed up for the defense of her crown by winning the Rome title on Sunday, dropping just one set and 22 games all week.
It was a return to the form that helped Williams win 11 titles in 2013 and proof, if any were needed, that the fire within burns as ferociously as ever as she returns to the city she calls her second home chasing an 18th major singles that would tie her with Chris Evert and Martina Navratilova.
The former French Open champion Li Na is probably her main rival as the Chinese attempts to become the first player since Jennifer Capriati in 2001 to win the year's first two slams.
Maria Sharapova, winner in 2012 and runner-up last year, will also be confident of a strong run after beating Li on the way to claiming the Madrid title earlier this month.
Poland's gritty world No.3 Agnieszka Radwanska, and Serbian duo Jelena Jankovic and Ana Ivanovic, the champion in 2008, will also be strong contenders while Simona Halep, the aggressive Romanian baseliner who has blasted into the top four, is more than capable of causing an upset.
Whoever Williams faces, however, she will not be feeling any extra pressure just because she is defending champion.
"Usually I'm like, 'Oh my God, I have to defend'. This time I'm going to be cool with it," Williams, who has bought a second Paris apartment near the Eiffel Tower, said recently when looking ahead to the French Open.
"I've been feeling that way for a while now. I think that's a good way to feel, since I won so many titles last year."
Ominously for her rivals, Williams's previous two French Open triumphs came following a title run in Rome.
Former semi-finalist and reigning Wimbledon champion Marion Bartoli, now retired, said Williams's match temperament was her biggest asset and the reason that she still sets the standard.
"I'm so impressed with how focused she is going into every grand slam," Bartoli, who will work as a pundit for ITV and Eurosport this year, told Reuters.
"She doesn't act like she's a favorite. She is just focused on winning every single match which is why she is a champion. She goes into every match thinking she needs to play her best tennis, not that she's the favorite."
Gone are the days, it seems, when a teenager would jump out of the pack to capture a grand slam.
World number two Li is also 32 and, like Williams, appears to be still improving. She showed with her magnificent 2011 run in Paris when becoming the first player from an Asian country to win a grand slam singles title that she has the tools and the temperament to survive two weeks of claycourt battles.
A second-round defeat last year to American Bethanie Mattek-Sands left her at a low ebb but she rebounded impressively, reaching at least the quarter-finals in 13 of her next 14 tournaments and winning this year's Australian Open.
"I'm feeling pretty good," Li said during her run to the quarter-finals of Rome last week. "I'm playing some high-quality matches. And I'm feeling pretty loose - I'm just going to do my best out there."
Sharapova, now comfortable sliding around on clay after looking clumsy on it earlier in her career, will benefit from being slightly under the radar this year after a shoulder injury meant a slow start to the year.
The former world No.1, now down at eighth in the WTA rankings, returned to her best form once the claycourt season started, winning back-to-back titles in Stuttgart and Madrid.
"I've done a really good job of transitioning from the hard to the clay and really improving physically and recovering well from match to match," the Russian told the WTA's website.
"I've benefited from that in the last couple of years. I enjoy playing on all surfaces. But I'm really happy about changing my results on clay the last few years."
A dark horse for the title could be Romanian Halep - the most improved player on the Tour in the last couple of years.
Wins against Ivanovic and Petra Kvitova on the way to the final in Madrid would have given her plenty of confidence as she bids to avoid a hat-trick of first-round exits at Roland Garros.
"Last year I was top 20, now I'm top five so its a big difference," she said. "I'm enjoying this time because it's the best in my career."
(Reporting by Martyn Herman; editing by Robert Woodward)