Charleston (US), April 12 (IANS): Sania Mirza and Martina Hingis survived a tough test to reach the final of the Family Circle Cup tennis tournament here on Saturday.

The No.1 seeded Sania and Martina beat 6-4, 1-6, 10-7 Alla Kudryavtseva and Anastasia Pavlyuchenkova in a rain-affected semi-final.

If they win the title, Sania will be the new World No.1 tennis player in women's doubles.

Waiting for them in the final are Casey Dellacqua and Darija Jurak, who got past Marina Erakovic and Andrea Petkovic in the second doubles semi-final 6-4, 1-6, 10-5.

The Indo-Swiss pair were up 6-4, 0-2, 30-all, when rain started - and once the rain interruption was over, their opponents Alla Kudryavtseva and Anastasia Pavlyuchenkova began playing well.

"It's never easy to play with the rain delay," Sania said after the match.

"All credit to them, though - they came out more aggressive than us, and they won six straight points, it was like they were all over the place hitting winners from everywhere. But we knew we had to keep believing."

Kudryavtseva and Pavlyuchenkova cruised through the rest of that set, 6-1, and came out firing again in the match tie-break, going up 4-2 and, after Sania and Martina caught up, staying even to 7-all.

But that's when Sania and Martina dug deep to win three points in a row to close out the match.