Nadal, in his first tournament since winning the U.S. Open and completing the career Grand Slam, improved to 60-7 on the year with a 6-1, 6-4 victory over Ruben Bemelmans.
Nadal lost only eight points over nine service games and didn't face a break point in the match. He won 24 of the 26 points when he landed his first serve.
While the top-seeded Nadal advance into the quarterfinals, second-seeded and world No. 8 Fernando Verdasco was beaten by Benjamin Becker 6-4, 6-4. Verdasco dropped serve three times in losing to Becker for only the second time in six career matches.
Jarkko Nieminen also pulled off an upset, ousting seventh-seeded Viktor Troicki 7-6 (7-4), 6-2, earning a quarterfinals match against third-seeded Jurgen Melzer.
Mikhail Kukushkin won a shot at Nadal in the quarters with a 6-4, 5-7, 6-3 win over Olivier Rochus.
In addition to the Nadal-Kukushkin and Nieminen-Melzer pairings Friday, fourth-seeded Ernests Gulbis will face Guillermo Garcia-Lopez and Becker plays Daniel Brands.
Copyright 2010 United Press International