Li Na, of China, returns a shot against Sofia Arvidsson, of Sweden, during the second round of the 2013 U.S. Open tennis tournament, Wednesday, Aug. 28, 2013, in New York. (AP Photo/Kathy Willens)NEW YORK (AP) — Li Na bought her work completed quick Wednesday at the U.S. Open, so when the rain started falling, she had little to fret about.