NEW YORK - Iga Swiatek and Casper Ruud will play defending champions Sara Errani and Andrea Vavassori on Wednesday night for the U.S. Open mixed doubles title and $1 million. Swiatek and Ruud, the No. 3 seeds, beat top-seeded Jessica Pegula 3-5, 5-3, 10-8 in a match tiebreaker in the first semifinal, in what was probably the best match of an event that was overhauled this year. They trailed 8-4 in the tiebreaker after Swiatek double-faulted, then ran off six straight points to advance.