DOHA, Qatar - What began as a walk in the park became one of the most dramatic matches of the week Thursday, as Caroline Wozniacki regrouped after blowing a 60 52 lead and fought off cramping in the third set to outlast Vera Zvonareva, 60 67(3) 64. 
Highlights: Wozniacki vs. Zvonareva
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Wozniacki, the No.4 seed, won 11 of the first 13 games against a discouraged Zvonareva, who got into the White Group as an alternate after Dinara Safina's withdrawal a day before. But the Russian summoned the form that took her to the final of the season finale a year ago, rallying to even it up at a set all, even saving two match points at 5-6. Shot of the Day: Vera Zvonareva.
After a 10-minute break due to the heat rule Wozniacki came out strong again, building a 3-1 lead in the third. But the leg that caused her to withdraw from Luxembourg last week began hurting again and as she began struggling with her movement Zvonareva began surging again, winning four of the next five games to take a 4-3 lead. But the Dane wasn't done, holding then breaking for 5-4, then fighting off severe cramps - and the subsequent tears - to serve it out.
"I should have finished it off after being up, 60 52, and after that she just started to play really well, really aggressive," Wozniacki said. "I feel great that I won under these conditions though. I have absolutely no idea how I pulled it through, but I'm very happy about it. And after the match I got to cool down, get a massage... the medical staff was helping me. I'm going to do everything to recover for my next match." Interview: Caroline Wozniacki
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It was Wozniacki's second marathon win in two days: on Wednesday she rallied from a first set blowout and match point to beat Victoria Azarenka, 16 64 75.
