Federer Takes Down Isner At U.S. Open

John Isner didn't lose his serve here for more than two years -- until Roger Federer ended an astonishing run of 110 consecutive service wins Monday night at the US Open.

The No. 2-seeded Federer took down Isner 7-6 (0), 7-6 (6), 7-5, finally breaking him in the last game. The 6-foot-10 American couldn't break the 17-time Grand Slam champion -- not even once.

As a result, Federer, a five-time US Open winner, is into the quarterfinals for the 11th time in 12 attempts. On Wednesday, he'll play Richard Gasquet, a four-set winner over Tomas Berdych. Federer has won 14 of 16 matches with the Frenchman.

"He's an unbelievable talent, a great shot-maker," Federer said of Gasquet. "I'm aware of the test ahead."

Federer has won all 12 of the sets he has played so far at the Billie Jean King National Tennis Center.

Serena Williams will face older sister Venus in a highly anticipated US Open quarterfinal Tuesday night following her 6-3, 6-3 victory over Madison Keys. Earlier Sunday in Arthur Ashe Stadium, Venus dispatched Estonian qualifier Anett Kontaveit 6-2, 6-1 in a fourth-round match that required only 50 minutes.

Thus Serena will have to go through Venus to get one step closer to a rare calendar-year Grand Slam. A win against her sister would leave Serena only two matches away.

"She's playing great," Serena said of Venus in her on-court interview. "I barely had time to get ready for my match because she won so fast. I have to be ready for that. At least a Williams will be in the semis, so that's good."

Steffi Graf was the last player, male or female, to achieve the Slam, 27 years ago. Before that, it was Margaret Smith Court (1970) and Maureen Connolly (1953).