Sania Mirza [Images] faces her biggest battle so far at the US Open [Images] 2005 right now she steps in to the grand Arthur Ashe stadium to play Maria Sharapova [Images] in the fourth round of the women's singles.

Mirza is dressed in a bright pink shirt while Sharapova is in more summer colors, blie and green single piece dress. Sharapova is serving first.

Mirza is the underdog here, and no doubt, a sizeable portion of the crowd will be behind her -- that is the tradition at the Open, where most root for the lesser player, the only exception being when the higher seed is homegrown. 

In fact, Mirza has become quite a star in her own right, with CBS doing a short segment 'Beyond the Baseline' on Mirza and her status in India as a sporting icon. Mirza was quite candid about the difficulties being a tennis player in Inida, saying 'it's not the easiest thing, we don't have the best courts, the best coaches, the best guidance.'

Nonetheless, Mirza has come a long way from her 430 ranking two years ago to 42 at this Open. And she has fought three good battles on her way to the fourth round, including two grueling three-setters.

Today could be the biggest day in Mirza's career so far, if she can beat Sharapova or even if she can give the Russian a run for her money.

Here's looking at you, kid.

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