By Ed McGrogan, Tennis.com

It would be way too simple to say that this rollercoaster contest came down to Kaia Kanepi's mental shortcomings versus Caroline Wozniacki's physical limitations. Yes, Kanepi failed to serve it out four times -- and wasted four match points -- before ultimately prevailing, 6-1, 6-7 (3), 6-3. And yes, Wozniacki's inability to hit through her stronger opponent contributed to the 5-1 deficits she faced in all three sets.

But before this match is banished to the never-upload-to-YouTube pile, it must be said that it was Wozniacki's assertive play, when Kanepi grew tentative in the second set, that propelled her unlikely rally, and it was the Estonian's persistence that gave her a chance to capture the victory at all. Two years ago at Wimbledon, Kanepi let five match points go and never saw a sixth in a painful quarterfinal loss to Petra Kvitova. She was surely thinking of that when her fifth match point came today against Wozniacki. Something tells me she didn't mind winning the match on a Wozniacki error.

It was a fitting ending, of course, to a match of questionable quality. Still, before it got ugly, Kanepi raced to a 6-1, 5-1 lead, showing the fast forehands and big backhands that make her a popular dark horse pick in tournaments. Against Wozniacki, who can't match her pace, Kanepi's groundstrokes looked even heavier. And when Wozniacki childishly complained to the chair umpire about a misread ball mark -- which did look out on replays, and was shown out on NBC's unofficial review -- Kanepi looked better in that department as well. "Have you been to school?", Wozniacki asked the official during their stand-off. It wasn't Wozniacki's best day by a long shot.

But as quickly as Kanepi built her 5-1 second-set lead, she lost it, looking less able each game. If her shots weren't landing long or wide, they were boomeranged back by her scampering opponent -- Wozniacki played some admirable defense. She also showed some of her best offense on the day during this stretch, catching Kanepi off guard while slowly creeping back to level terms. It all looked for naught when, at 5-5, Kanepi halted Wozniacki's momentum by breaking her, but a lovely backhand cross-court pass from the Dane (off a pretty good Kanepi inside-in forehand) sent the set to the tiebreaker it warranted. There, Wozniacki's all-around game and focus were on full display, along with a funky two-handed slice drop shot winner. To a third they went.

At this point, I was ready to put all my chips in on Wozniacki. The pre-match script had played itself out: Wozniacki had been out-gunned, but had stayed alive long enough to win the mental battle, and Kanepi was now ready to fold. But Kanepi re-raised. Instead of playing a flat third set, she stormed ahead, perhaps a result of not holding the lead.

There was the matter, though, of Kanepi actually having to deal with the lead, which she was forced to up 5-1. Serving for the match in fading light, Kanepi dropped the first two points, and no one would have been surprised if another break, or two or three, was in the offing. Well, one came, shortly after a Kanepi double fault on her third match point. But at 5-3, Kanepi held, a plot twist if I ever saw one. Some might say this match was about who wanted it less. But the heart she drew in the clay (see photo, at top right) after her topsy-turvy performance suggests otherwise.

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