India's tennis sensation Sania Mirza went down fighting 6-4, 7-5 to Gisela Dulko of Argentina in the semi-finals of the USD 170,000 WTA Tour event in Pattaya on Saturday.

In the final, Dulko will meet Austria's Sybille Bammer who beat fourth seed Shuai Peng of China 6-4, 6-2 in the other semi-final.

Dulko won the first set after breaking Sania's serve at 4-4 and returned everything the fifth-seeded Indian threw at her.

Sania's frustration began to show midway through the second set after she over-hit a series of forehand drives, before committing two double faults at 5-5 to allow the Argentine to break her serve and reach her second tour final.

"I knew it was going to be tough -- every game was close," Dulko said after the match.

"I was very focused and I had to be there all the time, 100 percent, because she hits the ball so hard."