Her serve was shaky. Her hard-hitting opponent, Victoria Azarenka, was presenting problems, and so was the gusting wind. A couple of foot-fault calls added to the angst.
As a jittery Williams headed to the sideline after dropping a set for the first time in the tournament, she chucked her racket, which ricocheted onto the court.
When play resumed, in the crucible of a third set, Williams put aside everything and did what she does best: She came through in the clutch to win a major match. Facing her only test of the past two weeks, the No. 1-seeded Williams overcame No. 2 Azarenka 7-5, 6-7 (6), 6-1 on Sunday for her 17th Grand Slam championship.
"When you're always trying to write history, or join history in my case, maybe you just get a little more nervous than you should. I also think it's kind of cool, because it means that it means a lot to you. It means a lot to me, this trophy," Williams said, pointing her right hand at her fifth silver cup from the U.S. Open, "and every single trophy that I have."
That collection keeps growing.
Williams has won twice in a row at Flushing Meadows — beating Azarenka in three sets each time — and four of the past six major tournaments overall. Her 17 titles are the sixth-most in history for a woman, only one behind Martina Navratilova and Chris Evert, and the same total as the men's record-holder, Roger Federer.
"It feels really good to be in that same league as him," said Williams, who earned $3.6 million in prize money.
This one did not come easily, even though it appeared to be nearly over when Williams went ahead by two breaks at 4-1 in the second set. She served for the match at 5-4 and 6-5 — only to have the gutsy Azarenka, a two-time Australian Open winner, break each time.
Williams is 67-4 with a career-high nine titles in 2013, but two of those losses came against Azarenka.
A year ago, they played the first three-set women's final in New York since 1995. This time, they went the distance again, a total of 2 hours, 45 minutes, because Azarenka was superior in the tiebreaker.
"I got a little uptight, which probably wasn't the best thing at that moment," Williams said. "I wasn't playing very smart tennis then, so I just had to relax and not do that again."
So after the second set, Williams gave herself a pep talk.
She regrouped and regained control.
"In the third set, Serena really found a way to calm down and restart from zero and quickly erase what happened," said her coach, Patrick Mouratoglou.
Azarenka helped a bit, with two of her seven double-faults coming when she got broken to trail 3-1 in the third.
That pretty much sealed it, because Williams was not about to falter again.
"She's a champion, and she knows how to repeat that. She knows what it takes to get there. I know that feeling, too. And when two people who want that feeling so bad meet, it's like a clash," Azarenka said, pounding her fists together.
At the outset, though, the 15 mph wind that swirled in Arthur Ashe Stadium bothered Williams as much as Azarenka did.
"It wasn't pleasant," Azarenka said.
Williams caught service tosses. She grabbed at her skirt to keep it from flying up. Most troubling, she was thrown off by balls that danced oddly. Six of the first 16 points ended with unforced errors by Williams, which allowed Azarenka to go ahead 2-1.
Looking hesitant at times, Williams did not show the same dominance she had while dropping only 16 games during six victories through the semifinals.
"The wind was unbelievable today," Williams said. "It just got worse and worse. It just never let up."
She needed to adjust, and she did.
Her serve, as usual, made a big difference: Williams hit nine aces, one at 126 mph.
Still, four times, Azarenka was only two points from taking the opening set. At one such moment, with Williams serving at deuce after a double-fault, she was called for a foot fault, erasing what would have been a 121 mph ace. There was another foot-fault call in the second set, too. They brought back memories of the American's loss to Kim Clijsters in the 2009 semifinals, when Williams was docked a point, and later fined, for a tirade against a line judge over a foot-fault call.
There was no such outburst directed at officials this time, although there was that racket toss. After the call in the match's 10th game, Williams simply put a hand to her face, composed herself, and won the point with a down-the-line backhand she celebrated with a fist pump, some foot stomping and a yell of "Come on!"
Williams wound up holding there with a 104 mph ace, part of what seemed to be a match-altering stretch. She won five consecutive games and 16 of 18 points to take the first set and go up a break in the second.
"You could see she clicked," Mouratoglou said. "She realized she was not aggressive enough. She was letting Vika dictate too much, and all of a sudden, things completely changed."
Well, at least for a while.
Azarenka did manage to make competitive again, which shouldn't surprise anyone. She was, after all, 31-1 on hard courts entering Sunday, including a victory over Williams last month at Mason, Ohio.
But when it came time to close the deal yet again, Williams shined. She delivered six of the third set's eight winners and forced Azarenka into 15 miscues. Soon enough, Williams was hopping up and down after finishing with a service winner. She kept pumping her fist afterward, even while sipping from a water bottle.
"She really made it happen," Azarenka said. "In that particular moment, she was tougher today. She was more consistent, and she deserved to win."
Williams became the first woman to surpass $9 million in prize money in a single season, while topping $50 million for her career.
She also equaled Steffi Graf with five U.S. Open titles, one behind Evert's record of six in the Open era, which began in 1968. Williams never had won two consecutive U.S. Opens, but now she has, adding to the trophies she earned in New York in 1999 — at age 17 — then 2002 and 2008.
Those go alongside five from Wimbledon, five from the Australian Open, and two from the French Open, which she won this year.
"Being older, it's always awesome and such a great honour, because I don't know if I'll ever win another Grand Slam. Obviously I hope so," said Williams, who turns 32 on Sept. 26. "It's different now, because when I won earlier, it was just one or two or three or four. Now it's like 16, 17. It has more meaning (for) history, as opposed to just winning a few."
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