Seeded Americans John Isner and Jack Sock are in action Wednesday as the second round of the U.S. Open begins.
Also starting Wednesday: second-round play in women's competition. It all begins about 11 a.m. ET at the USTA Billie Jean King National Tennis Center in New York.
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Wednesday also brings second-round matches for top men's seed Novak Djokovic and top Canadian Milos Raonic, who is seeded fifth in the year's final major tennis tournament.
Canada's Vasek Pospisil is among players with day-opening matches.