NEW YORK -- She's 30 years old, almost ancient by the unflinching standards of professional tennis. Her long, lanky body doesn't recover the way it used to; she didn't play a match the two months between Wimbledon and this U.S. Open because her cranky knees wouldn't allow it.
So even with sister Serena and Justine Henin absent, Venus Williams wasn't the prohibitive favorite here. Defending champion Kim Clijsters, Maria Sharapova and Victoria Azarenka were the fashionable picks to win.
But some things never go out of style. Big serves and plenty of nerve to move forward can carry you a long way on the swift courts of Arthur Ashe Stadium. On Friday, shrieking with vintage ferocity, only a successful tiebreaker separated Venus Williams from an unlikely berth in the final -- when she suddenly, alarmingly showed her age.
Back-to-back double faults -- at the worst possible time -- cost her the pivotal extra session, like the yips that sometimes visit aging golfers when they're trying to sink an important 5-foot putt.
Williams, the No. 3 seed, never recovered, and the No. 2 Clijsters was a 4-6, 7-6 (2), 6-4 winner.
"It obviously means a lot to be in the final and the chance to defend my title from last year is a great opportunity," Clijsters said. "Beating Venus here last year and again this year, I was most happy I was able to rise to the occasion when I had to."
Clijsters has won five of seven matches against Zvonareva.
The 27-year-old Belgian has won 20 consecutive matches at the U.S. Open, a remarkable run; only Chris Evert's streak of 31 (1975-79) is longer.
Afterward, Venus addressed her lack of match fitness coming in.
"Obviously I didn't have as much time to train as many of the others," she said. "I started out really slow, just an hour a day. I had a good 10 days of practice before this event.
"I just wish I could have played the bigger points a little better."
Williams had lost her previous four matches with Clijsters, but she came out throwing heat and Clijsters, who is generally more disposed to hit winners from the security of the baseline, looked defensive. On several occasions, she busted out her signature sliding split -- a move that has been largely dormant since the onset of motherhood. Set point was textbook; Williams ripped a 120 mph serve, sprinted forward and closed it out with a big forehand.
Clijsters fought back, taking a 4-2 lead when her shot skipped off the line and Williams rifled an errant backhand. But with Clijsters serving for the second set, she temporarily lost her mind. A wild backhand, sprayed far wide, got Williams back on serve.
In the tiebreaker, Williams showed her age. After dumping a backhand into the net for a 0-1 deficit, she double-faulted twice (after just one through most of two sets). On her next two service points, she blew an overhead, missing it long, and made a fourth unforced error, another low backhand.
"Obviously the tiebreak is a little more pressure, and it's just -- it was just tough to start serving with the wind behind you in the tiebreak. On that side I was waiting a lot longer for the wind to stop blowing so you could get a good toss.
"Regardless, I've got to get it in and start the point."
Technically, as Clijsters walked to her changeover chair, the match was all square. Why did it feel like hers to lose?
Sure enough, Clijsters broke Williams in the third game, but serving at 4-3, she suffered some yips of her own. Clijsters double-faulted at 30-all, then sent a swinging forehand volley well long -- a horrible miss under the circumstances since she went for more than she needed to.
And then Williams gave it right back, double-faulting at 30-all, pushing a weak forehand volley, then watching helplessly as Clijsters blooped a sweet backhand lob over her head. When it bounced 2 feet inside the baseline, Williams staggered as if she'd been hit in the jaw. Clijsters managed to served out the match, sealing it with a backhand winner.
"I was hitting into wind; you can hit it harder and flatter," Clijsters said of the lob. "It's instinct, you decide to do it. And it worked."
A year ago at Arthur Ashe, Zvonareva was a disheveled mess. In the process of losing to Flavia Pennetta in the fourth round, she cracked her racket, angrily tore at the tape on both knees and openly sobbed.
It was this wrenching image that skewed the conventional thinking before Zvonareva met Wozniacki early Friday afternoon. Additionally, Wozniacki was riding some impressive numbers into the semifinals:
• 15-3 in four years at the U.S. Open.
• Found herself in the midst of a 13-match winning streak, including titles at Montreal (where she beat Zvonareva in the final) and New Haven.
• Had won 27 of her past 30 sets, including 10-for-10 in New York.
Wozniacki has won more matches (49) than anyone else on the Sony Ercisson WTA Tour, but she still hasn't beaten a top-five player in 18 months; Maria Sharapova was the only player ranked among the top 40 of her five victims here.
Still, Wozniacki was defying charges of overplaying when she ran into Zvonareva, a 26-year-old Russian who has blossomed relatively late in terms of tennis.
Zvonareva played in 28 Grand Slam events but never reached a final -- and now she's done it back to back, at Wimbledon and here in New York. She played bigger than Wozniacki (18 winners to 13) and made fewer unforced errors (25 to 31). Twenty of those errors came on the forehand. Zvonareva managed to break the Dane's serve four times.
"Last year is something that was in the past," Zvonareva said of her meltdown. "I had some experience last year, not only here at the U.S. Open, the whole year overall I played a lot of matches. I take that experience and I try to use it to my advantage. Never look back."
"A tough day for me in the office," Wozniacki said, "and unfortunately it was today. Just made a few mistakes and she took advantage of it."
Said Zvonareva of the final, "Any match with Kim will come down to the tough challenge. She's a great mover on the court. She has a lot of experience. She won here last year. It's going to be tough."
Venus played in three straight U.S. Open finals at the start of the recent century, winning in 2000 and 2001. She was trying to get back to the final for the first time in eight years. Her sister Serena, Henin and Clijsters all have won two titles since then, and Sharapova won the other. Venus had to content herself with dominance at Wimbledon (five titles).
Clijsters took the title in 2005, then missed the event with an injury and a two-year sabbatical from the game. Last year, she won again and now is in position to take her third crown in three attempts.
A year ago, she outslugged Serena in the semifinals, but that was overlooked in the wake of the foot-fault controversy.
"I always feel good here," Clijsters said. "If I can give myself the opportunity to get to the second week, play these kind of matches and not get surprised by opponents at the beginning of the tournament, anything is possible."
There are no peripheral issues this time. On Saturday, Clijsters could win her third consecutive U.S. Open title. And who will find fault with that?
Greg Garber is a senior writer for ESPN.com.