Kohlschreiber served nine aces and converted four of 11 break points.
Sixth-seeded Feliciano Lopez, the 2004 champion, defeated Austrian wild card Andreas Haider-Maurer 6-4, 6-4. Lopez conceded just three points on serve in the opening set. He dropped serve early in the second set before breaking twice.
Story continues below ↓advertisement | your ad hereMichael Berrer topped Steve Darcis of Belgium 6-3, 6-2. The German was added to the main draw as a replacement for defending champion Philipp Petzschner, who pulled out earlier Tuesday after injuring his left calf in training.
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