The win ran Nadal's clay-court match winning streak to 58 straight.
"I feel good," said the second-seeded Nadal. "I am playing high level this year than last year, no? I know I am a better player this year."
In the semifinals, Nadal will face No. 4 Ivan Ljubicic, who was a 6-2, 6-2, 6-3, winner over France's Julien Benneteau.
Ljubicic, who qualified for a Grand slam semifinal for the fist time in his career, had 13 aces and broke Benneteau's serve eight times.
Friday's other men's semifinal will feature top-seeded Roger Federer and No. 3 David Nalbandian of Argentina.