MIAMI, FL, USA - Former World No.1 Karolina Pliskova needed three tough sets to battle past the tricky Hsieh Su-Wei and take her spot in the Miami Open round of 16.

It was Pliskova’s first time playing the No.61-ranked Hsieh, who wreaked havoc on the Australian Open draw earlier in the season when she knocked out No.3 Garbine Muguruza on her way to a breakthrough round of 16 run.

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The No.5 seed recovered emphatically from a mid-match letdown, bouncing back from a one-sided second set to edge through 6-4, 1-6, 7-6(4) after almost two and a half hours on court.

“She has a strange game,” Pliskova admitted afterwards. “There’s not a lot of players who are playing like this with a lot of dropshots, a lot of slices. It was very tricky.”

Pliskova broke the Hsieh serve in the first game to start the match with a healthy 2-0 lead. Hsieh was doing her best to absorb Pliskova’s pace and return the flat, heavy shots with some of her signature spins and slices. Her unconventional style occasionally troubled Pliskova, but Hsieh couldn’t prevent her from breaking once more at 4-1.

With Pliskova closing in on the set, Hsieh took advantage of a dip in the Czech’s intensity to finally broke back as she was serving for it at 5-2. Hsieh was threatening a comeback, reeling off three games in a row and even earning a break point to make it 5-5. But Pliskova tamped down the Taiwanese player’s resistance and recovered admirably, batting away the break point and closing it down.

Despite dropping the opening set, Hsieh carried her positive momentum into the second set as Pliskova’s form continued to dip - the Czech’s first serves clocked in at 38%, down from 65% in the first set - and the unforced errors crept into her game.

Hsieh kept her groundstrokes low, catching the 6’1” Pliskova at the knees and drawing out the errors, Pliskova recording 12 in set two alone - twice as many as Hsieh. Pliskova could only hold serve one time as Hsieh soared ahead to take the second set 6-1.

The pair stayed toe-to-toe for most of the second set, the first seven games going to the server. Former World No.1 Pliskova finally broke through at 5-3 after a marathon game featuring three break chances, but Hsieh replied by emphatically saving three match points to break her straight back.

Pliskova wracked up three more match points across the next three games, but Hsieh refused to yield, holding up against the pressure to send them into a tiebreaker. But Hsieh’s great defending seemed to crumble in the decider as Pliskova got ahead to a double mini-break lead, 5-1. Even as she crept back into the tiebreak, Pliskova finally converted on her seventh match point to close out the tiebreaker 7-4.

Up next, Pliskova will take on Zarina Diyas for a spot in the quarterfinals. A victory would be only Pliskova’s second quarterfinal appearance in Miami, and the first since 2015.