Add Serena Williams to the list of big names eliminated early at this wild and unpredictable Wimbledon.

The defending champion failed to close out a seesaw third set Monday, dropping the last four games against Sabine Lisicki of Germany to lose 6-2, 1-6, 6-4 in the fourth round and end her career-best 34-match winning streak.

"I'm still shaking," Lisicki said in a postmatch interview, covering her face with her hands to wipe away tears. "I'm just so happy."

It was the latest in a string of upsets that has jolted the tournament, with defending championRoger Federer and Rafael Nadal knocked out in the first three days -- along with Maria Sharapova andVictoria Azarenka's withdrawal on the women's side.

Sloane Stephens of the U.S. reached her second Grand Slam quarterfinal of the year, beating 19-year-old Monica Puig of Puerto Rico 4-6, 7-5, 6-1.

The 17th-seeded Stephens is the last American singles player left at the grass-court tournament.

Williams looked to be cruising after dropping the first set, winning nine straight games to take a 3-0 lead in the third. The players then traded breaks to give Williams a 4-2 lead, but the American couldn't win another game -- despite having four break points at 4-3.

Those would have given her a chance to serve for the match. Instead, Lisicki held, broke again and converted her second match point with a forehand winner.

Williams gave credit to Lisicki's dominant serve, which she said consistently reached 120 mph.

"On the grass, with the surface being a lot faster, it's going to be more difficult to break her," Williams said.

Read it at ESPN.