Sania Mirza [Images] pulled off the biggest win of her fledgling career when she upset world number 7 and US Open champion Svetlana Kuznetsova in straight sets 6-4, 6-2 and moved into the quarterfinals of the Dubai Open women tennis championship on Tuesday.

Sania, a wild card entrant, showed great character and played some solid tennis to upset her much higher ranked opponent in the second round of the high-profile tournament being played at the Dubai Tennis Stadium.

India's new sporting star

Sania underlined her potential against Kuznetsova, recovering from a shaky start to produce a supremely confident performance.

The match initially looked like being a major embarrassment for Sania, who attracted nearly 5,000 spectators consisting mainly of expat workers to the centre court.

She lost the first game to love in 42 seconds as the fourth-seeded Russian fired two aces, and fell behind 4-0 after suffering an ankle injury.

She received several minutes of treatment but double-faulted twice at 3-0 as she experienced problems serving.

"My ankle was killing me," said Mirza. "It was the third time it has happened in the last three weeks. I was actually crying because I was in so much pain.

"But I took a pain killer and I think it took a couple of games for me to get used to the taping, and the pain killers started working 15 or 20 minutes after that."

The match turned dramatically, however, when Sania banished her nerves and began to hit the ball sweetly from all angles.

After winning six straight games to take the first set Sania continued to grow in confidence and forcing a forehand error from Kuznetsova to break in the first game of the second set.

Although the Russian immediately broke back to level at 1-1, she failed two win three game points in the next game before Sania broke again.

Urged on by the boisterous crowd, Sania continued to pound the ball at every opportunity and her efforts were rewarded with the best win of her career.

Kuznetsova said she had been caught cold in her first match of the tournament.

"I had pressure and couldn't get into the games," Said Kuznetsova. "She was playing great, but I didn't do what I had to do.

"I didn't attack at all. I had to make her play more points and I had to make her move. I still have so much to learn.

"It's a big upset but I'll try to keep my head up and still work hard."

Sania will face 28th seed Jelena Jankovic in the quarterfinal. Jankovic beat Silvia Farina of Italy [Images] 4-6, 7-5, 6-1.

In other matches, Daniela Hantuchova [Images] took advantage of some uncharacteristic errors from sixth seeded Australian Alicia Molik [Images] to win 7-6, 6-2, while Elena Likhovtseva needed nine match points and two hours 38 minutes to overcome Tunisia's Selima Sfar 2-6, 6-2, 7-6.

Seventh seed Nathalie Dechy of France [Images] struggled before edging past Russian qualifier Vera Douchevina 6-7, 6-4, 7-6, and Na Li of China beat Japan's [Images] Ai Sugiyama 1-6, 7-6, 6-2.

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