Serena Williams beat Maria Sharapova for the 15th consecutive time, rallying in both sets Thursday for a 6-4, 6-3 victory in the Sony Open semifinals.

Williams is seeking a record seventh Key Biscayne title. She improved to 16-2 against Sharapova and hasn't lost to her favorite foil since 2004.

The No. 1-ranked Williams won with a superior serve and better returns. She hit nine aces and broke five times, helping her rebound from deficits of 4-1 in the first set and 2-0 in the second.

Williams earned her 14th consecutive victory against a top-10 player. Her opponent in Saturday's final will be the winner of the semifinal Thursday night between reigning Australian Open champion Li Na and Dominika Cibulkova.