Former world number one Marat Safin signalled that he could threaten the favourites for the French Open title after brushing aside Spain's Fernando Vicente 6-1, 6-3, 6-1 on Sunday to reach the second round.
The Russian, a semi-finalist in 2002 but beaten in the first round last year, needed just one hour, 24 minutes to advance.
"I need to get the rhythm and the timing in order to play good tennis," he said. (But) I think I can manage to pass two rounds and, if I do, then I'm going to be dangerous."
He added that champion Rafael Nadal or world number one Roger Federer would win the tournament.
The unseasonably cold and wet weather in Paris meant only seven of the scheduled 24 matches were completed on the opening day of the claycourt grand slam.
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