Juan Martin del Potro of Argentina and former champion Juan Carlos Ferrero of Spain were among the early winners at the French Open on Sunday in Paris.
The ninth-seeded del Potro beat Spaniard Albert Montanes 6-2, 6-7 (5-7), 6-2, 6-1 at the world's lone clay-court major. Del Potro was a French Open semifinalist in 2009.
Ferrero, whose only Grand Slam title came back in 2003 on the famed red clay at Roland Garros, defeated Frenchman Jonathan Dasnieres de Veigy 6-1, 6-4, 6-3.
Croatian Marin Cilic, the No. 21 seed, handled Daniel Munoz-De La Nava of Spain 6-4, 6-4, 7-5. Cilic will face Ferrero in the second round.
German Cedrik-Marcel Stebe was leading Joao Souza 6-3, 2-0 when the Brazilian retired.
French crowd favorite Jo-Wilfried Tsonga and American Andy Roddick are also on Sunday's schedule. Tsonga will open against Russia's Andrey Kuznetsov, while Roddick will likely have the crowd against him when he meets Frenchman Nicolas Mahut.
Six-time champion Rafael Nadal beat 2009 winner Roger Federer in last year's final to capture a second straight French Open title. Nadal shares the men's record, along with Bjorn Borg, with his six Open Era championships here.
Nadal has been the runner-up to Novak Djokovic in the last three Grand Slam finals overall, including this year's Australian Open.
The 2012 Roland Garros titlist will win $1.57 million.