WASHINGTON - Chinese Taipei's tennis player Hsieh Su-wei upset former world number one and No 13 seed Caroline Wozniacki from Denmark at the Miami Open on Monday to reach her first quarterfinal at Premier Mandatory level.

Hsieh, seeded 27th in the event, edged past Wozniacki 6-3, 6-7(0), 6-2 in the fourth round match in two hours and 15 minutes.

In four previous meetings with the Dane, Hsieh had won just one set, but they had not played since the 2015 Kuala Lumpur semifinals. Now the 33-year-old Hsieh has become an upset artist, also beating world number one Naomi Osaka from Japan in previous round at Miami.

Last month, a run of upsets to the Dubai semifinals sealed Hsieh's biggest ever run at a Premier 5 event, and now she's proving herself at an even higher level.

Hsieh started the match strongly with an early break, but Wozniacki broke back to level the scores. The 33-year-old Hsieh combined clever lobs and wrong-footing groundstrokes to make her opponent run all the time. In the 7th and 9th games, Hsieh broke Wozniacki to take the opening set.

Wozniacki began the second set more positively, storming to a 3-1 lead. But once again, Hsieh was able to find another level and reel off four of the next five games. In the tiebreak, Wozniacki won seven straight points to take the set.

In the deciding third set, Hsieh took control of the game and broke twice to take a 4-0 lead. After that, Hsieh never looked back. In the set, Hsieh once again demonstrated her idiosyncratic use of touch and finesse, including unbelievable dropshot and angled volley.

Hsieh will in the quarterfinals take on Estonia's Anett Kontaveit, who is seeded 21st in the event.