Victoria Azarenka needed to win the second set twice. She had plenty left to pull away for a three-set victory at the U.S. Open.

The second-seeded Azarenka took 2 hours, 40 minutes to close out Alize Cornet 6-7 (2), 6-3, 6-2 in the third round Saturday.

Serving on game point at 5-3 in the second, Azarenka pumped her fist and started walking off the court after the 26th-seeded Cornet hit a backhand into the net. The chair umpire had to get her attention to inform her that the line judge had called Azarenka's previous shot out — replays showed it landed inside the baseline. The umpire overruled the call, but they still had to replay the point.

"Are you freaking kidding me?" Azarenka howled to the chair ump. "What the hell are you doing?"

After the match, she put it this way: "That was the most ridiculous thing there is."

On her second try at set point, Azarenka hit a forehand wide to send the game to deuce. But she won the next two points to clinch the set, after all.

Then she dominated the third to advance to face 13th-seeded Ana Ivanovic, who rallied to beat young American Christina McHale in three sets.

"The dynamic of the match was a little bit weird for me," Azarenka said. "I felt like I didn't take my opportunities in the first set, which was kind of a waste and it gave her a lot of confidence, and she really came up with the great shots when she needed with the big serves. I'd actually never seen her serve like that before, so that's definitely a big improvement from her side."

Nadal still cruising

Rafael Nadal has barely been pushed so far at Flushing Meadows. The second-seeded Spaniard posted his third straight-set victory, beating Ivan Dodig 6-4, 6-3, 6-3.

Nadal has faced only five break points, saving all of them, through three matches. But he doesn't think that's because he's serving particularly well.

"I am winning because I am playing well from the baseline and I am making the right decisions in the right moments," Nadal said.

He'll next face 22nd-seeded Philipp Kohlschreiber, who beat the top American man, John Isner, at this stage for the second straight year. Isner's 6-4, 3-6, 7-5, 7-6 (5) loss means the host country has only one player left in the men's draw.

Federer races past Mannarino

Quick as can be, Roger Federer moved into the fourth round at the U.S. Open for the 13th year in a row with a 6-3, 6-0, 6-2 victory over Adrian Mannarino.

Finishing points with early winners from all angles, 17-time Grand Slam champion Federer raced past the Frenchman in only one hour and 21 minutes.

"There's always a lot of pressure coming out here on this court to perform, because you never know if you're going to play well," said Federer, who compiled a 34-8 edge in winners, "but tonight was one of those nights."

Mannarino said: "He was playing too good for me, that's for sure. ... I was making a lot of mistakes, but that's because of Roger. He's playing too fast."

Federer, who won five consecutive U.S. Opens from 2004-08, next plays 19th-seeded Tommy Robredo of Spain. Federer has won all 10 of their previous matches.

If Federer makes that head-to-head record 11-0, he could face 12-time major champion Rafael Nadal in the quarterfinals in what would be the rivals' 32nd meeting — but first at Flushing Meadows. Not only have they met at each of the other Grand Slam tournaments, they've met in the final at Wimbledon, the French Open and Australian Open.

Against Mannarino, Federer had no trouble with the swirling wind in Arthur Ashe Stadium, whipping deep returns off the left-handed Mannarino's soft second serves and winning 36 of 39 points on his first serve.

"I was able to really use my serve well, because it was breezy tonight again. I used the wind a bit better and I had more variation than him, which gave me more margin in my game," Federer said. "I won the first set and I was able to play with the lead, and that makes things easier, as well."

Federer has been ranked No. 1 for more weeks than any man in history, but he's currently No. 7, his lowest spot since 2002. He has won one title in 2013, dealt with pain in his lower back and experimented with using a larger racket head.

And his record streak of reaching the quarterfinals at 36 straight Grand Slam tournaments ended with a second-round loss at Wimbledon to an opponent ranked outside the top 100.

So far at the U.S. Open, though, he has looked good. It's the 56th consecutive major tournament Federer has entered, tying the men's record held by Wayne Ferreira.

Promising generation

Even with McHale's tough loss, it's still been a promising tournament for the generation of U.S. women who must succeed the Williams sisters.

A day after she and Venus won their second-round doubles match, Serena Williams gets a much-anticipated rematch with 20-year-old Sloane Stephens on Sunday. They're joined in the round of 16 by a less expected American, wild card Alison Riske.

Maybe Riske's run isn't that much of a surprise considering her recent surge. The 23-year-old Pittsburgh native came into the summer having never accomplished any of these feats: winning a match in a Grand Slam tournament, at a WTA Tour event on hard courts, or against a top-10 foe.

She's now achieved all that, her latest breakthrough victory a rout of 2011 Wimbledon champ Petra Kvitova. Riske won 6-3, 6-0, taking the last eight games against the seventh-seeded Czech, who was in bed with a fever the day before.

"I've got a new confidence in myself," the 81st-ranked Riske said through tears in an on-court interview. "I believe that I belong here."

Ivanovic survives

McHale was one game away from matching Riske in upsetting a former major champion to reach her first Grand Slam fourth round. The 21-year-old had a chance to serve out the match at 5-4 in the second set, but Ivanovic broke back.

The 2008 French Open champ then saved two break points at 5-5, and she broke McHale's serve in the next game to clinch the second set.

Ivanovic broke McHale again in the final game of the third set for a 4-6, 7-5, 6-4 victory in 2 hours, 26 minutes.

McHale has been ranked as high as 24th, but she'd slipped to No. 114 after a bout with mononucleosis.

"After some of the losses I've had this year, even though today it hurts to lose this type of close match, I feel much better about my game," she said.

Riske was 0-5 at major tournaments before Wimbledon this year but is 5-1 since. She just broke into the top 100 in late July; now Riske will likely earn a top-60 ranking.

She has always thrived on grass, making the third round at Wimbledon this year. Now she's starting to figure out the hard courts. She next faces Daniela Hantuchova, while other fourth-rounders set up Saturday are No. 10 Roberta Vinci against unseeded Camila Giorgi in an all-Italian match, and No. 21 Simona Halep against Flavia Pennetta. The 136th-ranked Giorgi defeated 2009 U.S. Open runner-up Caroline Wozniacki, who was seeded sixth, 4-6, 6-4, 6-3 at night.

Kvitova said she tried to end points quickly, knowing she couldn't hold up through long rallies. But Riske stayed calm and played good defence, taking advantage of Kvitova's seven double-faults and 27 unforced errors.

"She moved quite well," Kvitova said. "She pushed me to the back. That was tough for me."

It's another frustrating finish at Flushing Meadows, the only major tournament at which Kvitova hasn't made the semifinals. Two years ago, she became the first reigning Wimbledon women's champion to lose her first U.S. Open match in the same season.

"My body wouldn't let me fight," Kvitova said.

Saturday's session opened with two minor upsets: Simona Halep, seeded 21st, crushed No. 14 Maria Kirilenko 6-1, 6-0, and Flavia Pennetta beat 27th-seeded Svetlana Kuznetsova 7-5, 6-1. The two face each other in the next round.

The 21-year-old Halep extended a sizzling summer with her first trip to a Grand Slam fourth round. She's coming off a title at New Haven.

On the men's side, fourth-seeded David Ferrer needed nearly three hours to down 172nd-ranked qualifier Mikhail Kukushkin 6-4, 6-3, 4-6, 6-4. His next opponent is No. 18-seeded Janko Tipsarevic, who also took four sets to knock off 20-year-old American Jack Sock 3-6, 7-6 (1), 6-1, 6-2.

Eighth-seeded Richard Gasquet and No. 10 Milos Raonic set up another fourth-round matchup with victories.