Caroline Wozniacki outlasts Maria Sharapova at U.S. Open

Caroline Wozniacki trusts her stamina so much that she plans to return to New York in two months to run a marathon.

Maria Sharapova, usually the one wearing down opponents in the third set, sure couldn't keep up on a steamy Sunday at the U.S. Open. Wozniacki won 6-4, 2-6, 6-2 in 2 hours, 37 minutes to get back to her first Grand Slam quarterfinal in more than two years — and get back in the headlines for reasons other than her personal life.

"It's been an up and down year for me," Wozniacki said in quite the understatement.

With the fifth-seeded Sharapova's loss, No. 1 Serena Williams is the only woman left in the top six.

Because of the heat, the players were given a 10-minute break before the final set; Sharapova returned to the court late, arguing with the chair umpire after receiving a time violation warning. Sensing that she was fresher than the five-time major champion, Wozniacki later complained that Sharapova was dawdling between points.

Her tardiness seemed to swing the Arthur Ashe Stadium crowd's support squarely in Wozniacki's favor. When the 10th-seeded Dane broke Sharapova at love to go up 3-1 in the final set, she got a standing ovation from the fans and waved her arms to egg them on.

Wozniacki's defensive style is faulted as the reason that the former top-ranked player has made only one major final. But it worked to perfection as Sharapova wilted. On the last point of that game, Sharapova appeared to hit a winner three times only for Wozniacki to somehow chase down the ball. Sharapova finally hit a volley into the net to end the rally.

Wozniacki broke her again to end the match. About a half-hour later, play was halted at Flushing Meadows because of thunderstorms in the area.

As a 19-year-old, Wozniacki made the 2009 U.S. Open final, losing to Kim Clijsters, and reached No. 1 in the world the next year. Since then, she was best known for getting engaged to star golfer Rory McIlroy — then getting dumped in late May after wedding invitations had gone out.

Wozniacki lost in the first round at the French Open soon thereafter and was upset in the fourth round at Wimbledon. She had been playing much better since, though, winning her first title in nine months at Istanbul then dropping a pair of three-set matches to Williams.

Meanwhile, Wozniacki announced a month ago she planned to run the New York City Marathon on Nov. 2, somehow squeezing in training during a busy fall season. Seems to be working out well mentally and physically on the tennis court.

Unlike the women's draw, the men's side didn't lose a top-10 player until Sunday, when fourth-seeded David Ferrer was upset by Gilles Simon in the third round. Simon won 6-3, 3-6, 6-1, 6-3 to set up a meeting with 14th-seeded Marin Cilic, who beat Kevin Anderson.

Wozniacki will next face 13th-seeded Sara Errani, who ended the run of qualifier Mirjana Lucic-Baroni with a 6-3, 2-6, 6-0 victory.