Sony Ericsson Open 4th seed, Elena Dementieva, joined seeds 2, 3 and 5 today; she was upset by 13th-seeded Caroline Wozniacki, 7-5, 6-4. Top seed Serena Williams was taken to three tough sets by Zheng Jie, but she survived, and--in doing so--won her fiftieth Sony Ericsson Open match.
The day's other upsets were performed by Samantha Stosur, and by Iveta Benesova, who defeated Anabel Medina Garrigues.
Other 4th round winners were Venus Williams, Svetlana Kuznetsova, Victoria Azarenka, and Li Na. Williams defeated Agnieszka Radwanska. What little I saw of this match was quite enjoyable, but Radwanska was clearly affected by nerves toward the end.
I saw all of the match between Li and Ekaterina Makarova, which was an inconsistent affair from the beginning. Li should have swept the first set, but she made so many unforced errors that she wound up in a tiebreak, which Makarova won easily. Makarova then took a medical break to deal with a thigh problem. She was never the same after that. Whether her thigh was giving her a bit of trouble or whether she just wasn't up to being in the 4th round in Miami, I don't know. (Her service game decreased in quality, which may have been a result of the thigh pull.) But it was all Li after the first set, and she won 6-7, 6-2. 6-2.