National champion Saina Nehwal [Images] advanced to the semi-finals of the Singapore Open badminton tournament, beating Indonesia's Firdasari Adrianti 21-16, 20-22, 21-16 on Friday.

In a fierce contest that lasted 47 minutes, the Olympics [Images] qualified Saina pocketed the first game but squandered the lead and went down 20-22 in the next game.

However, she got her act together in the decider and held her nerve at crucial moments to seal the third game and match 21-16.

The victory set up a tough last four clash with fifth seed and Athens Olympics bronze medallist Mi Zhou of China on Saturday.

Zhou beat third seeded compatriot Chen Wang 21-17, 21-19 in the other quarter-final.

Saina had beaten qualifier and local favourite Juan Gu 21-19, 21-17 to enter the quarter-finals on Thursday, even as compatriots Anup Sridhar and Arvind Bhatt crashed out of the men's singles in the second round.

Sridhar lost to Sairul Amar Ayob of Malaysia 17-21, 13-21 while Bhatt was beaten by Joachim Persson of Denmark 11-21, 27-25, 15-21.