Second-seeded Novak Djokovic and No. 4 seed David Ferrer won their quarterfinals matches Thursday at the U.S. Open in Flushing Meadows, N.Y., and face each other in the semifinals of the tennis Grand Slam tournament.
Djokovic won in straight sets, 6-2, 7-6, 6-4 over Argentina's Juan Martin Del Potro to end Day 11 of the tournament. Before Djokovic's victory, Ferrer outlasted eight-seeded Janko Tipsarevic in five sets, 6-3, 6-7, 6-2, 3-6, 7-6 in a match that lasted some 4 hours, 41 minutes. The last set took 82 minutes alone.
Ferrer had six double-faults to his opponent's zero but also won the battle of services aces, 15-10.
Djokovic hit 43 winners to Del Potro's 25 in their match. The winner of Djokovic-Ferrer faces the winner of the Andy Murray-Tomas Berdych match in the U.S. Open final this weekend.
The women's singles semifinals take place Friday. It's top-seeded Viktoria Azarenka vs. No. 3 seed Maria Sharapova, and No. 4 seed American Serena Williams against the surprise semifinalist, 10th-seeded Sara Errani of Italy.
The No. 2-seed Bryan brothers, Bob and Mike, play for the men's doubles title against Leander Paes and Radek Stepanek, the fifth-seeded team.