PARIS (AFP) - Serena Williams, the 2002 French Open winner, and defending champion Ana Ivanovic, insisted on Friday that recent injury problems, which overshadowed their Roland Garros build-up, are behind them. World number two Williams hobbled out of her opening match in Madrid last week having failed to recover from a knee injury which played a large part in earlier, successive defeats in Marbella and Rome. It means she hasn't won a match on clay since last year's French Open when she was knocked out in the third round by Katarina Srebotnik. "I feel fine now. I don't have any regrets about playing in Madrid," said 27-year-old Williams who called it quits in the Spanish capital after losing the first set to Italy's Francesca Schiavone. She had also taken the opportunity to criticise the WTA's policy on playing commitments, insisting that she would still have to go on to court even 'if I was dead'. Williams, the winner of 10 Grand Slam titles, believes her injury problems could work in her favour in Paris. "I don't think I am the favourite. It is what it is. Now I feel I want to make all my memories this year. "I am more confident than I was a couple of weeks ago so that's a step in the right direction." Williams starts her ninth French Open against the Czech Republic's Klara Zakopalova, the woman who put her put in the first round in Marbella. Ivanovic, a popular winner in 2008 before a brief spell as the world nunber one, is looking for a repeat of the Roland Garros magic. The Serbian, who is seeded eight this year, skipped the Madrid Open because of a knee injury but said she is back to full fitness as she looks ahead to a first round clash with Italy's Sara Errani. "I'm fine. I had a few problems in Rome with my knee. I had some scans and saw the doctors. I feel 100 percent now. I have an osteopath with me here and we are still working on it. I feel healthy again." Ivanovic is also aware of the potential dangers posed by the Williams sisters in what many believe will be one of the most open Roland Garros tournaments in recent years. "If Serena is playing, I'm sure she will be at 100 percent and that she's ready to compete," she said. "Both Williams are great champions and always perform well at the big events."