Martina Hingis produced a regal display to overcome a spirited late challenge from former Israeli cadet Tzipora Obziler and sail into the quarter-finals of the US $175,000 WTA Sunfeast Open in Kolkata on Wednesday.

The world No 9 won 6-2, 7-5 to set up a clash with Thailand's Tamarine Tanasugarn, who prevailed over the United States' Abigail Spears 2-6, 6-3, 6-2 in another second round match earlier at the Netaji indoor stadium.

The first set was tougher than what the scoreline suggests, but it was in the second that the Israeli really stretched the tournament top seed.

However, displaying the quality that marks out giants, Hingis raised her game when it mattered most to put it across her opponent and end the 85-minute face-off.

The 3,000-odd crowd that had turned out to watch the centre court tussle were treated to some electrifying shots from Hingis, who also regaled with her swift movements and excellent court coverage.

The opening set saw Obziller come close to breaking Hingis in the fourth game but the former world number one held serve.

Hingis broke Obziller in the very next game, and that launched her on a four-game winning streak including another service break in the seventh game to close the set.

Obziller, however, seemed more determined in the second set and straightaway demolished Hingis in the opening game.

However, the title favourite drew level by breaking back in the very next game.

Obziller, riding on some measured placements, again broke Hingis in the seventh game, but suffered the same fate in the next as the set score became 4-4.

The ninth game was a cliffhanger, as Hingis put pressure on Obziller's serve gaining four breakpoints, but the Israeli retained serve as Hingis hit a backhand into the net.

Hingis had little difficulty holding her serve in the tenth game, before launching a determined assault on Obziller in the next game, which she won on the third break point.

The rest seemed a cakewalk for the fancied player who won the next game in style without conceding a point.

A trademark backhand down the line winner from Hingis signaled it was all over for the Israeli as the crowd broke into thunderous applause.