TOKYO, Jan 31: Former world number one Martina Hingis became the first player to reach the quarter-finals at the Pan Pacific Open tennis tournament when she outclassed Nicole Pratt on Wednesday.

The Swiss second seed, seeking a record fifth Tokyo indoor title, missed two match points leading 5-4 in the second set.

But she hit her fourth ace to convert her third match point, beating the Australian qualifier 6-1, 7-5 in a 66-minute contest.

In the quarter-finals on Friday, Hingis will take on either sixth seed Li Na of China or another Australian, Samantha Stosur, the winner over Vera Zvonareva of Russia 6-4, 6-7 (4/7), 6-4.

Li was a convincing 6-2, 6-2 winner over American Lilia Osterloh on Tuesday.

In other first-round action, Maria Kirilenko of Russia whipped up-and-coming seventh seed Shahar Peer with a 6-2, 6-3 victory.

“Before the match I had very good concentration. I played against her a lot of years ago, but I beat her 6-0, 6-0. Now I think I did the same,” said Kirilenko.

In the second round on Thursday, Kirilenko will play former world doubles number one Ai Sugiyama of Japan, who outplayed Elena Vesnina of Russia 6-4, 6-2.

China's Zheng Jie breezed past American Bethanie Mattek 6-2, 6-1, while Mara Santangelo of Italy overwhelmed Japan's Aiko Nakamura 7-5, 6-0. Elena Likhovtseva of Russia was a 6-3, 6-2 winner over Gisela Dulko of Argentina.

Results (x denotes seeds):Played on Wednesday

First round: Zheng Zie (CHN) bt Bethanie Mattek (US) 6-2, 6-1; Mara Santangelo (ITA) bt Aiko Nakamura (JPN) 7-5, 6-0; Samantha Stosur (AUS) bt Vera Zvonareva (RUS) 6-4, 6-7 (4/7), 6-4; Elena Likhovtseva (RUS) bt Gisela Dulko (ARG) 6-3, 6-2; Maria Kirilenko (RUS) bt Shahar Peer (ISR) 6-2, 6-3; Ai Sugiyama (JPN) bt Elena Vesnina (RUS) 6-4, 6-2

Second round:

Martina Hingis (SUI x2) bt Nicole Pratt (AUS) 6-1, 7-5

Played on Tuesday:

First round: Ana Ivanovic (SCG x7) bt Shenay Perry (US) 6-4, 6-2; Roberta Vinci (ITA) bt Daniela Hantuchova (SVK x8) 6-4, 6-4; Nicole Pratt (AUS) bt Meghann Shaughnessy (US) 6-7 (4/7), 6-1, 6-4; Li Na (CHN x6) bt Lilia Osterloh (US) 6-3, 6-2; Severine Bremond (FRA) bt Marion Bartoli (FRA) 6-0, 6-2; Francesca Schiavone (ITA) bt Erika Takao (JPN) 7-5, 7-5. –Agencies