Sixth seed Juan Martin del Potro eased past German Benjamin Becker 6-2 6-4 6-2, while French seventh seed Jo-Wilfried Tsonga battled to a straight-sets win over Japan's Go Soeda.
Becker's other tips to make an impression are U.S. Open champion Juan Martin Del Potro and fifth seed Andy Murray of Britain, who has yet to win a grand slam.