From Charles

Tennis authorities are looking into a match involving Caroline Wozniacki, the United States Open runner-up, because of a surge in betting. Wozniacki retired from the match at the Luxembourg Open with a hamstring injury Wednesday while leading Anne Kremer, 7-5, 5-0. Wozniacki’s father, Piotr, told her at 3-0 in the second set to retire before winning because her injury would keep her from playing in the next round. His comments were heard by Internet viewers, and there was a surge in online bets for Kremer to win.