The Dane, seeded 10th, sealed her place in the quarter-final of the year’s final Major after a thrilling 6-4, 2-6, 6-2 over Maria Sharapova in 2 hours and 37 minutes to reach her first last-eight match in two years.
24-year-old Wozniacki, who reached the US Open final in 2009 but has never won a Grand Slam crown, faces 13th Italian seed Sara Errani for a place in the semi-final last this week.
However, Wozniacki won’t take to the Arthur Ashe court until after Federer’s fourth-round match against 17th-seeded Roberto Bautista Agut of Spain, who beat Adrian Mannarino 7-5, 6-2, 6-3.
@rogerfederer please try and not play too long, I am on after you
— Caroline Wozniacki (@CaroWozniacki) September 1, 2014
Federer has won the US Open on five previous occasions (2004, 2005, 2006, 2007 and 2008).
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