Serena Williams will be playing her fifth Australian Open after winning a grueling semifinal match against Li Na, 7-6 (4), 7-6 (1).

Williams won the second-set tiebreaker, sealing the set with an ace.

During the first tiebreaker, Williams got four of her last five points from unforced errors care of a fatigued Li. The American took advantage of the mistakes and finished the tiebreaker with a second-service ace.

History is on the side of Serena as she has a perfect record in Melbourne Park finals. She won the tourney in 2003, 2005, 2007, and 2009.

She will be matched up against either Zheng Jie or Justine Henin on Saturday.