MELBOURNE, Australia(AP) Defending champion Serena Williams has won her third-round match at the Australian Open, beating Carla Suarez Navarro of Spain 6-0, 6-3.

The top-seeded Williams, who beat Dinara Safina in last year's final, emerged from a marathon final game in Saturday's opening set, facing five break points and 13 deuces before winning on her eighth set point. The final game lasted nearly 20 minutes - longer than the five previous games combined in the 37-minute set.

Williams closed out the match in 1 hour, 21 minutes and will face Sam Stosur of Australia in the fourth round. Stosur beat Alberta Brianti of Italy 6-4, 6-1.