Now that the big upsets have happened, U.S. Open fans have two questions: Who is next to fall, and when will it occur?
Goodbye, Milos Raonic. Adios, Garbine Muguruza. Later, Svetlana Kuznetsova.
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Will Vania King add to the list? That's one huge assignment, given her Thursday match is against No. 1 seed Serena Williams. Venus Williams also plays on Thursday, in a second-round match expected to begin about 3:30 p.m. ET.
An early match to watch: No.