The second semifinal between defending champions Sara Errani/Andrea Vavassori and the all-American, last-minute alternate pairing of Danielle Collins/Christian Harrison is underway, as they bid to join Świątek/Ruud in the mixed doubles finale.

NEW YORK (Reuters) -Italians Sara Errani and Andrea Vavassori retained their mixed doubles title at the U.S. Open on Wednesday, overcoming Iga Swiatek and Casper Ruud 6-3 5-7 10-6 in the competition's reimagined format that drew some of the top singles players.