NEW YORK (AP) The U.S. Open is underway in steamy conditions.
Rafael Nadal isn't around to defend his title because of a right wrist injury. Top-ranked Serena Williams is seeking her third straight championship on the women's side.
Second-seeded Simona Halep, fourth-seeded Agnieszka Radwanska and sixth-seeded Angelique Kerber are among the players with early matches Monday.
Andy Murray, Stan Wawrinka, Venus Williams and Sloane Stephens will also be on court during the day session. Maria Sharapova and Novak Djokovic play at night under the lights at Arthur Ashe Stadium.