Zverev topped Florent Serra 6-2, 7-6 (8-6) and Minor came from behind to beat Nicolas Mahut 5-7, 6-3, 6-3.
Spain's Albert Montanes defeated another French player, outlasting Nicolas Devilder 7-6 (7-5), 7-5.
The tournament is a tuneup for the U.S. Open, which starts Aug. 25.
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