Rafael Nadal emerged a 6-4, 6-3 winner over Jarkko Nieminen with no obvious discomfort to his troublesome left knee as the Spaniard began his quest for a record eighth title at the Monte Carlo Masters on Wednesday.
Nadal, now 40-1 at the venue where he lost his only match in 2003, won his 38th straight game in the principality as he overcame stubborn resistance from the Finn ranked 48th who claimed the Sydney title in January.
Nadal, who required two weeks of knee treatment after failing to play his Miami semi-final match due to pain, has not lifted a trophy since the French Open ten months ago.
"I played a really normal match, nothing special - nothing very bad, but nothing very good," said Nadal.
"It was the first match on clay after long time, and the first match after 15 days without touching a racquet.
"The imprtant thing was that I won in straight sets. Tomorrow I have another chance to keep improving, and that's what I'm going to try.
"You need days to see how all the sensations improve: the knees, the tennis, everything. When you stop for 15 days without practise, your body loses a little bit the performance."
The second seed joined world number one Novak Djokovic in moving through a clay-season opener in straight sets on a cloudy day on the Mediterranean coast.
Djokovic began with a 6-1, 6-4, victory over Andreas Seppi. taking a 5-0 lead over the 44th-ranked Italian and breaking for an early lead in the second on the way to his seventh win in the series.
"I served really well when I needed to," said Djokovic. "That's encouraging for the clay, it's good to have a couple of free points there.
"I was really focused first set and played it well against a tough, quality opponent who plays good on clay. For the first official match since Roland Garros last year, it was satisfying."
The top seed will next play 16th seed Alexandr Dolgopolov, who put out new Monte Carlo resident Bernard Tomic 6-2, 5-7, 6-1.
"He's a very talented player, comes up with some shots that are not really typical," said Djokovic of Dlogopolov. "He changes the pace and is very dangerous on clay,
"I need to be aware and disciplined on the court. I need to try not to be frustrated with the rhythm that he comes up with."
There was a shock for fifth seed David Ferrer as the Spaniard went down to Thomaz Bellucci of Brazil 6-3, 6-2.
Number six Tomas Berdych dismissed Croatian Marin Cilic 7-6 (7/3), 6-1, with Serb number seven Janko Tipsarevic advancing over Spain's Albert Montanes 6-2, 6-3.
Number eight Nicolas Almagro beat Italian Potito Starace 7-6 (7/3), 6-1 while number nine Frenchman Gilles Simon won a match that began at the early hour of 10:30, beating Frederico Gil of Portugal 6-3, 6-0.
Julien Benneteau registered a French win as he put out 2011 semi-finalist and 15th seed Jurgen Melzer 6-4, 6-3. Mikhail Kukushkin beat Italy's Filippo Volandri 7-6 (10/8), 2-6, 6-2 and Switzerland's Stanislas Wawrinka beat Pablo Andujar 7-5, 6-3.