Qualifier Milos Raonic, coming off a fourth-round appearance at the Australian Open, dumped Lu 6-3, 6-3. Raonic had nine aces and didn't face a break point as he won 86 percent of the points on serve, losing six points in his nine service games.
Dustin Brown took out Serra in 55 minutes, winning 6-4, 6-4. Brown pounded 15 aces and converted 3-of-11 break-point chances. He lost only 13 points over 10 games on serve.
Fourth-seeded Kevin Anderson rallied for a 4-6, 6-4, 6-2 win over Stephane Bohli while No. 6-seeded Adrian Mannarino needed to win a pair of tiebreakers in beating Yuri Schukin 7-6 (7-4), 7-6 (8-6) and eighth-seeded Michal Przysiezny romped over Martin Fischer 6-1, 6-2.
Also Tuesday, Denis Gremelmayr beat Nikala Scholtz 6-4, 7-5 and Izak Van der Merwe defeated Stephane Robert 6-3, 6-2.
Third-seeded Janko Tipsarevic and Jesse Huta Galung were tied 7-6 (7-4), 4-6, 3-3 when rain caused play to be suspended.