Nadal, seeded third this week, is seeking his ninth consecutive tournament championship in the event. He began his title defense with a 6-1, 6-2 romp over Marino Matosevic in 62 minutes.
Nadal won 72 percent of the points on serve and more than 60 percent off Matosevic's serve. Matosevic managed a break to grab a 2-0 lead in the second set but Nadal ran off the next six games and advanced to the third round.
World No. 1 Novak Djokovic, still having problems with an ankle injury, was pushed to a third set before coming away with a 4-6, 6-1, 6-4 win over Mikhail Youzhny. Second-seeded Andy Murray stopped Edouard Roger-Vasselin 6-1, 6-4 with four breaks in eight receiving games.
Jurgen Melzer and Jarkko Nieminen pulled off upsets Wednesday. Melzer eliminated 10th-seeded Nicolas Almagro 6-4, 6-2 without dropping his serve. Nieminen defeated No. 12-seeded Milos Raonic 3-6, 6-1, 7-6 (7-3). He won about three-quarters of the points on serve in the second and third sets.