Feliciano Lopez of Spain and Russia's Mikhail Youzhny were among the winners Monday in the first round of the Swiss Open.
The fifth-seeded Lopez, runner-up at this event in 2006, toppled Czech qualifier Jan Hernych, 7-6 (7-2), 6-3, while the sixth-seeded Youzhny went the distance in a 6-3, 4-6, 6-2 triumph over 2007 Gstaad champion Paul-Henri Mathieu of France.
Spain's Marcel Granollers, the 2011 champ, also won his first-round match Monday with a 6-2, 6-4 rout of seventh-seeded Czech Lukas Rosol.
Russian Andrey Kuznetsov advanced Monday with a 7-5, 3-6, 6-2 victory over Ukrainian Sergiy Stakhovsky. Kuznetsov will face Lopez in the second round.
The clay court tournament is led by native Swiss stars Roger Federer and Stanislas Wawrinka. Both have byes into the second round.
Federer, who lost to Stakhovsky in the second round at Wimbledon, is playing this event for the first time since winning the title in 2004. Wawrinka reached the final in 2005 and lost to Gaston Gaudio.
Thomaz Bellucci of Brazil won last year's title, beating Serbia's Janko Tipsarevic in the final. Bellucci, also the winner in 2009, will play his first-round match against Argentina's Federico Delbonis, who just stunned Federer in the Hamburg semis this past weekend.