And yet, she explained afterward, "I really was preparing my runner-up speech."
No need for that. When the going gets toughest, Williams tends to shine.
Finally tested, and even trailing, at Flushing Meadows, Williams suddenly found her composure and her strokes, winning the last four games for a 6-2, 2-6, 7-5 victory over top-ranked Victoria Azarenka on Sunday night, collecting a fourth U.S. Open championship and 15th Grand Slam title overall.
"I never give up. I never, never quit," Williams said after the first three-set U.S. Open women's final since 1995. "I have come back so many times in so many matches."
In other ways, too.
She missed eight months after having surgery on her left knee in 2003, the year she had completed a self-styled "Serena Slam" by winning four consecutive major titles. Of more concern: Only a few days after winning Wimbledon in 2010, Williams cut both feet on broken glass while leaving a restaurant in Germany, leading to two operations on her right foot. Then she got clots in her lungs and needed to inject herself with a blood thinner. Those shots led to a pool of blood gathering under her stomach's skin, requiring another procedure in the hospital.
In all, she was off the tour for about 10 months, returning in 2011.
"She was so disgusted at home. She felt like she was useless. That's the way it is with athletes, I guess. She couldn't sit still," said Williams' mother, Oracene Price. "She was getting depressed. A lot to overcome."
Talk about making up for lost time.
Take a look at what Williams has done lately. Back on May 29, she lost to a woman ranked 111th at the French Open, the American's only first-round exit in 49 career Grand Slam tournaments.
"I was miserable after that loss in Paris. I have never been so miserable after a loss," Williams said. "I pulled it together. ... Sometimes, they say, it's good to lose."
Certainly in her case.
Since then, Williams is 26-1, including titles at Wimbledon, the London Olympics and the U.S. Open.
"She's definitely the toughest player, mentally, there is," said Azarenka, who managed only 13 winners, 31 fewer than Williams. "And she's got the power."
Forget what the rankings say. Williams, who was seeded fourth, is dominating the game right now. And she's been dominant, off and on, for more than a decade.
She won her first major title age 17 at the 1999 U.S. Open. Winning titles 13 years apart at the same Grand Slam tournament represents the longest span of success in the professional era, which began in 1968. Martina Navratilova (Wimbledon, 1978 and 1990) and Chris Evert (French Open, 1974 and 1986) had the longest previous spans of 12 years.
"Yeah, three decades — the '90s, 2000s, 2010s," said Williams, who turns 31 on Sept. 26. "That's kind of cool."
She is the first woman in her 30s to win the U.S. Open since Navratilova in 1987.
Williams also showed a more mature side Sunday, avoiding the sort of flare-ups at officials that got her in trouble during her last two trips to the U.S. Open.
"This is the first year ... in a long time," Williams said, "I haven't lost my cool."
In the 2009 semifinals, Williams was angered by a foot-fault call that resulted in a double-fault, setting up match point for her opponent, Kim Clijsters. Williams launched into a racket-brandishing tirade that resulted in a fine and a Grand Slam probation. While losing to Sam Stosur in last year's final, Williams berated the chair umpire after being docked a point for making noise during a rally.
This time, there was a foot-fault call, too. Williams didn't react at all immediately, finished off that game, then stared down the linesman as she walked to the sideline at the ensuing changeover. He chuckled a bit.
"I'm just happy that she got through this one without any incident and was able to try to forget all that in the past," Price said. "Because I think that was a lot in her mind."
Actually, by then, Williams had bigger problems to worry about.
She double-faulted to get broken in second set's opening game, and got broken again to fall behind 4-1 in a game that featured Azarenka sliding into a running forehand winner and nearly doing a full splits. Even Williams applauded that one.
But when the game ended, Williams slapped her racket against her changeover chair.
That set was the first Williams had lost all tournament; she'd only dropped a total of 19 games through her first six matches.
While Azarenka, a 23-year-old from Belarus, doesn't have the name recognition or bona fides of Williams, she did win the Australian Open in January, and was 32-2 (a .941 winning percentage) on hard courts in 2012. She also hadn't dropped a three-setter all season until Sunday, going 12-0 in matches that went the distance, including victories over defending champion Stosur in the quarterfinals and 2006 winner Maria Sharapova in the semifinals.
As Sunday's deciding set commenced, Price told her daughter from the stands, "Settle down."
Didn't happen right away.
"Well, she's a human being, you know, who has two feet, two legs, two hands," Azarenka said. "It's understandable."
When Williams double-faulted, slapped a bad backhand into the net and pushed a forehand long, Azarenka broke at love for a 4-3 edge, then followed that up by holding for 5-3.
One game from the championship.
Azarenka was within two points of victory at 30-all in the next game, on Williams' serve, but couldn't convert. When Azarenka served for the victory at 5-4, she showed the jitters that probably are understandable given that this was only her second career Grand Slam final, 17 fewer than Williams.
Azarenka made three errors in that game, including a forehand into the net that let Williams break her to 5-all. Williams kept whatever excitement she might have felt contained, face straight as possible, while her older sister, seven-time major champion Venus, smiled and clapped in the stands.
That was during a key stretch in which Williams took 10 of 12 points to go ahead 6-5. She then broke again to win, dropping onto her back on the court when Azarenka sent a backhand long to end it.
"Feels like there is no room for a mistake," is the way Azarenka described trying to deal with Williams' game. "There is no room for a wrong decision."
Azarenka, now 1-10 against Williams, slumped in her changeover chair, a white towel covering her head. Williams, meanwhile, kept saying, "Oh, my God! Oh, my God! Oh, my God!" while scurrying over to share the joy with her mother and big sister.
"Being so close, it hurts deeply," Azarenka said. "To know you don't have it. You're close; you didn't get it."
After her first-round loss at Roland Garros, Williams went back to work, getting help from Patrick Mouratoglou, a coach who runs a tennis academy in France. She's 14-0 in Grand Slam matches since then; the Wimbledon trophy ended a two-year drought without a major title.
Mouratoglou came to New York with Williams, and he noticed the way she set aside her mid-match struggles.
"Players usually completely lose their confidence and they can't get all of their tennis back. But she got all her tennis back. Like nothing happened," he said. "This is what was most impressive. She's not like the other players."
It's the fourth time in five years that the women's final was pushed from Saturday to Sunday because of bad weather — Novak Djokovic faces Andy Murray in the fifth consecutive Monday men's final — and when play began, Williams was good as can be, compiling a 16-2 advantage in winners through the first set.
She pounded big serves — she finished with 13 aces, at up to 125 mph — and big returns; smacked forehands and backhands out of Azarenka's reach; even tossed in a terrific backhand lob to break for a 2-0 lead at the outset.
But her unforced errors really started arriving in waves in the second set, then kept coming in the third, and Williams ended up with 45 in all, 17 more than Azarenka.
Deep in the match, with everything at stake and the finish so near, Williams was the one who was steadier.
No one should be surprised by that.
She is the first woman to win Wimbledon and the U.S. Open in the same season since 2002, when — yes, that's right — Williams did it.
Now she will set her sights on raising her Grand Slam title total to 18, the number Navratilova and Evert each won, tied for fourth-most behind Margaret Court at 24.
"I haven't thought about them until recently. I never thought I would even come close to breaking those records," Williams said. "If I could win two a year, it would be great. We'll see."
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