Comfortable win for Nadal
Rafael Nadal kicked off his quest for an historic eighth consecutive Monte Carlo Masters title with a 6-4 6-3 win over Jarkko Nieminen.
Nadal has not won a tour-level title since last year's French Open and is cautious over his chances of extending his winning streak at Monte Carlo, where he first won the title in 2005.
Nadal told atptour.com: "We need to see how all the sensations improve - the knees, the tennis, everything. I need practice, and today was a good practice.
"Tomorrow is another tough match against an opponent who is dangerous."
Nadal will play Mikhail Kukushkin in the third round, after the world number 68 from Kazakhstan fought back to beat Italy's Filippo Volandro 7-6 (10-8) 2-6 6-2 in two hours and 17 minutes.
The Mallorcan was joined in the third round by world number one Novak Djokovic, who required just two minutes longer than Nadal to secure a 6-1 6-4 victory over Italy's Andreas Seppi.
Next up for Djokovic is Ukrainian 16th seed Alexandr Dolgopolov, who had to work rather harder to secure his passage with a 6-2 5-7 6-1 win over Australian youngster Bernard Tomic.
Last year's losing finalist David Ferrer, seeded fifth, was a shock casualty as he fell 6-3 6-2 to Brazilian Tomaz Bellucci, but
Tomas Berdych and Janko Tipsarevic made it safely through with wins over Marin Cilic and Albert Montanes respectively.
Eighth seed Nicolas Almagro was a 7-6 (7-3) 6-1 winner over Italian wild card Potito Starace, and there were also wins for Gilles Simon, Stanislas Wawrinka, Kei Nishikori, Julien Benneteau and Robin Haase.