Serena Williams held off a stiff challenge and Amelie Mauresmo was forced to rally, but both advanced to the US Open third round Wednesday. Williams beat Lindsay Lee-Waters, 6-4, 6-3, and Mauresmo came back from a set down to defeat Julia Vakulenko, 3-6, 6-2, 6-2. Other winners include Lleyton Hewitt, David Nalbandian, Sebastien Grosjean, Elena Dementieva and Vera Zvonareva. Gustavo Kuerten and Fernando Gonzalez lost their opening-round matches in four sets, and Angela Haynes upset veteran Magdalena Maleeva, 6-2, 6-3. Jennifer Capriati and Roger Federer are in action tonight.