NEW YORK (AP) — Can’t count out Serena Williams, no matter how big the deficit, no matter how off-target her strokes, no matter how much the pressure might be mounting as she bids for a calendar-year Grand Slam.

Serena Williams returns a shot to Bethanie Mattek-Sands during the third round of the U.S. Open tennis tournament, Friday, Sept. 4, 2015, in New York. (AP Photo/Julio Cortez)

Eight times this season at major tournaments, Williams has dropped the opening set. Eight times, she has won.

The latest comeback was in the third round of the U.S. Open on Friday night, when Williams figured out a way to deal with a tricky opponent and get her own game going before it was too late, eventually emerging to grab the last eight games for a 3-6, 7-5, 6-0 victory over American wild-card entry Bethanie Mattek-Sands.

“I’m not trying to live on the edge,” Williams said with a big smile.

Perhaps. Still, no one does it better. And with so much at stake, no less.

“She’s a great closer,” Mattek-Sands said. “Always has been.”

The No. 1-ranked Williams is trying to become the first tennis player since Steffi Graf in 1988 to win all four Grand Slam tournaments in the same season. She won the Australian Open on hard courts in January, the French Open on clay courts in June, and Wimbledon on grass courts in July, and now is four wins away from adding the trophy on the hard courts of the U.S. Open.

Add in her title last year in New York, and Williams is bidding for a fifth consecutive Grand Slam title and 22nd overall, which would equal Graf for the second-most in the professional era, which began in 1968, and second-most in history behind Margaret Court’s 24.

Serena Williams reacts after winning a point against Bethanie Mattek-Sands during the third round of the U.S. Open tennis tournament, Friday, Sept. 4, 2015, in New York. (AP Photo/Julio Cortez)

So it’s understandable that Williams acknowledged feeling “tight” and “nervous” in her second-round victory Wednesday, when she immediately headed out to the practice courts for extra work with coach Patrick Mouratoglou.

And that probably explains the look of relief on Williams’ face as she walked to the net to shake hands with Mattek-Sands, quite a contrast to all of the screams of “Come on!” and fist pumps during the match.

Some of Williams’ most vociferous reactions came down the stretch — including when her momentum carried her all the way over to Mattek-Sands’ side of the net after a long sprint to reach a drop shot and, in the next game, when she hit a cross-court forehand passing winner and dropped down, doing the splits behind the baseline, shaking both fists.

Next up for Williams is a fourth-round match Sunday against yet another American, 19th-seeded Madison Keys.

Looking down the line, Williams’ quarterfinal opponent could be older sister Venus, who reeled off the last five games to beat 12th-seeded Belinda Bencic of Switzerland 6-3, 6-4.

Did Venus get any family advice before facing Bencic, who is responsible for one of Serena’s two losses in 53 matches in 2015?

“Yes, but that’s between us,” Venus said, breaking into a wide smile. “I think it worked.”

In men’s action, No. 1 Novak Djokovic and defending champion Marin Cilic moved into the fourth round, while Rafael Nadal hoped to join them in the night’s closing match. Two top-10 players lost — No. 7 David Ferrer and Nol 10 Milos Raonic — and No. 14 David Goffin, citing stomach problems, became the 13th man to retire during a match because of injury or illness.

There were moments Friday under the lights of Arthur Ashe Stadium when it appeared that Mattek-Sands, who is ranked 101st as she comes back from two hip operations, would end Williams’ 30-match Grand Slam winning streak.

While Mattek-Sands won doubles titles this year at the Australian Open and French Open, this was a rare moment in the spotlight for her in singles. She had appeared in the U.S. Open 13 other times, never making it as far as the third round until this week at age 30.

But by mixing in slices with flat strokes, heading to the net when there were openings — and even sometimes when there weren’t — Mattek-Sands played a varied, attacking game that gave Williams fits for nearly two full sets.

“She went for everything. She played her style, her ‘Bethanie Mattek-Sands tennis,’” said her husband, Justin Sands, who offered kudos to Williams for “her fight, her determination, her will to win. You know you’re going to be in a dogfight. She is never, ever out of a match.”

That was the case on this night, despite particular problems on break points: Williams was able to convert only 3 of 16 through the first two sets, before going 3 of 5 in the third.

“I said, ‘You know what, Serena? Just keep going,’” said Williams, who also has a chance to become the first woman since Chris Evert in 1975-78 to win four U.S. Opens in a row. “‘Keep trying, keep trying, keep trying.’”


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