The tennis world number one Novak Djokovic and defending champion Rafael Nadal reached the Monte Carlo Masters third round after straightforward victories in the season's first big claycourt tournament.
Nadal beat Finland's Jarkko Nieminen 6-4 6-3 while Djokovic defeated Italian Andreas Seppi 6-1 6-4.
Last year's finalist David Ferrer, the fifth seed, suffered a shock 6-3 6-2 loss to Brazilian Thomaz Bellucci.
The second seeded Spaniard Nadal will next play Kazakhstan qualifier Mikhail Kukushkin.
Serbia's Djokovic, who is chasing Nadal's French Open crown after winning the last three grand slam events, will take on 16th seed Alexandr Dolgopolov, who beat Australian teenager Bernard Tomic, in the third round.