Unforced errors and poor serve cost Sania Mirza [Images] and Mahesh Bhupathi [Images] dearly as the Indian duo squandered numerous chances before surrendering the Australian Open mixed doubles title to fifth seeds Tiantian Sun and Nenad Zimonjic in Melbourne on Sunday.

The unseeded Indian pair went down 6-7 (4), 4-6 to the Chinese-Serbian pair in the close to one and half hours contest.

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Sania and Bhupathi only had themselves to blame for the loss as they were a break up at 4-3 in the first set before they allowed the fifth seeds to claw their way back into the match.

The unseeded pair broke Sun and Zimonjic once more in the engrossing opening set but their failure to hold their own serve stretched it to a tie breaker, where the fifth seeds came out trumps.

The Indians were especially weak in their second serve and a couple of double faults only compounded their woes in the 42-minute opener.

Having lost the first set closely, Sania and Bhupathi failed to bounce back in the second set, committing more double faults and unforced errors.

In contrast, Sun and Zimonjic were pumped up after going a set up and broke the Indians once besides holding their own serve without conceding a single break point.

To their credit, Sania and Bhupathi saved seven break points, including three match points. But it was all but over by that time as Sun and Zimonjic, serving for the match, romped home with ease.

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