Key Biscayne, Florida: Serena Williams returned to tournament tennis after a two-month absence and beat Zhang Shuai of China 6-2, 6-3 at the Sony Ericsson Open on Thursday.
No. 2-seeded Maria Sharapova overcame 12 double faults and erased 10 break points to rally past Shahar Peer of Israel 4-6, 6-3, 6-3, while No. 4 Caroline Wozniacki beat Barbora Zahlavova Strycova 6-4, 6-0.
Two-time champion Kim Clijsters defeated No. 14-seeded Julia Goerges of Germany 6-2, 7-5. No. 13 Jelena Jankovic lost her opening match to Mona Barthel of Germany 6-0, 6-3.