MONTE CARLO, Monaco (AFP) - Reigning Roland Garros champion Stan Wawrinka began perhaps the most important clay season of his tennis career, with a 7-6, 7-2 (7-5) defeat of Philipp Kohlschreiber on Wednesday at the Monte Carlo Masters.

World No. 4 Wawrinka, who also won the title at the seaside Monte Carlo Country Club over Roger Federer in 2014, will line up in the third round against French 15th seed Gilles Simon.

The Swiss took 96 minutes to advance over the German, who fought off the Wawrinka attack as he saved 10 of 13 break points against his serve.

Wawrinka will be trying to build momentum on clay this spring as his May return date to the French Open draws closer.

He finally finished with a break in the second set for 6-5 and claimed victory a game later on his first match point, to take his record over Kohlschreiber to 4-0. It was Wawrinka's second defeat of the German this season after Dubai in February.

The 31-year-old Wawrinka is one of only four men to have disrupted the Big Four's trophy dominance of Masters 1000 titles since Monte Carlo 2010. Fifty of the last titles in the series have been won by either Novak Djokovic (23), Rafael Nadal (12), Roger Federer (eight) or Andy Murray (seven).

Wawrinka is part of an elite spoiler's list also comprising Robin Soderling (Paris-Bercy 2010), David Ferrer (Paris-Bercy 2012) and Jo-Wilfried Tsonga (Toronto 2014).

Elsewhere, French 16th seed Benoit Paire defeated Joao Sousa of Portugal 6-4, 6-3 to reach the third round at his second consecutive Masters event after Miami last month.

Holder Djokovic and fifth seed Nadal were playing their opening matches, with top seed Djokovic facing Czech Jiri Vesely and eight-time Monte Carlo champion Nadal facing the 26-year-old Slovenian-born Briton Aljaz Bedene.