DOHA, Qatar - The two debutantes at the Sony Ericsson Championships - Doha 2009 went to battle in the first match on Wednesday and what a battle it was, as Caroline Wozniacki fought back from a first set blowout to beat Victoria Azarenka, 16 64 75.  Highlights: Wozniacki vs. Azarenka

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Azarenka, the No.6 seed at the season-ending event, came out firing early on, losing the opening game of the match but winning the next six straight, finishing the first set with 11 winners to just five unforced errors. The 80-minute second set featured some very tight games, including an incredible 14-deuce fifth game where Azarenka fended off seven break points to hold serve for a 3-2 lead. But Wozniacki kept on fighting, eventually breaking for 5-4 and serving it out.

With the heat rule in effect the players took a 10-minute break and Azarenka seemed refreshed, winning the first two games of the third set and eventually serving for the match at 5-3; although she was broken, she got to match point at 5-4, but missed a forehand long and eventually saw Wozniacki even things up.

After winning the first set so easily and squandering her chances in the third, Azarenka lost her cool at that juncture. After falling behind on her serve at 5-5, 15-30, she smacked a ball out of the stadium, drawing a warning from the umpire. After losing the next point to go down 15-40 she smashed her racquet, bringing her a point penalty that gave Wozniacki the break and a 6-5 lead. Wozniacki calmly served it out.  Shot of the Day: Caroline Wozniacki

"I just kept fighting," Wozniacki said after the two-hour, 58-minute battle. "The crowd, especially the Danish people here, helped me through this. I knew I had to step it up after the first set, otherwise she would just run over me. Now I just want to enjoy this great win."  Interview: Caroline Wozniacki

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In the second match of the day, Jelena Jankovic took on Dinara Safina and earned the win when Safina retired with a low back injury at 1-1 first set. Safina then withdrew from the tournament, thus surrendering the year-end top ranking - to Serena Williams. Vera Zvonareva will replace Safina in the White Group.

"I've had this pain in my back for about three months now. I was advised to take a break after the US Open but at Tokyo and Beijing, it didn't bother me that much," Safina said. "Then my body just gave up. I did everything possible to play here. I just couldn't handle the pain anymore."