OSAKA, Japan -- Hsieh Su-wei of Chinese Taipei pulled off an impressive comeback at the Toray Pan Pacific Open on Tuesday, saving a match point en route to a 3-6, 7-6(1), 6-1 victory over former World No.1 Garbiñe Muguruza of Spain.

World No.33 Hsieh fought back to clinch her second win in two meetings against 26th-ranked Muguruza, having also beaten the two-time Grand Slam champion in the second round of the 2018 Australian Open, when the Spaniard was ranked World No.3.

"I know that anything can happen because this is almost the end of the year," Hsieh said to the media, after the match. "I just want to be more relaxed, going more to my game. Sometimes I lose a little bit of rhythm at the beginning, so I just need to play more games to get the rhythm."

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After just over two hours of play, Hsieh notched her first-ever win at the event in her fourth appearance in the main draw. Hsieh finished the match with 26 winners, three fewer than Muguruza, but she also had six fewer unforced errors than the Spaniard. The player from Chinese Taipei also claimed nearly 60 percent of points off of Muguruza's second serve.

Muguruza has now taken her fifth straight loss, despite being one point away from a solid victory, breaking Hsieh six times, and firing six aces. Muguruza has not won a match since her third-round win over Elina Svitolina at Roland Garros.

"First set, [Muguruza] was hitting the ball very hard, and I was not expecting a game like this," Hsieh admitted. "I was still trying to find a way to get into the match."

"In the second set, I felt a little bit more rhythm, and more stable myself, my personal style," the winner continued. "It helped me a lot to get into the match and to get more game."

Hsieh will now take on Elise Mertens of Belgium in the second round. Mertens, who reached the US Open quarterfinals in her prior event, dispatched American lucky loser Whitney Osuigwe in the first round on Monday. Hsieh and Mertens have split their two previous meetings, both of which came last year.

The powerful play of Muguruza held her in good stead as the match commenced, and she earned a quick service break in the first game with a return winner. However, the double-handed wizardry of Hsieh pulled her back level at 3-3 with some well-placed backhands.

Muguruza, though, also exhibited some exceptional play from that wing, pummelling a barrage of backhands at her opponent to force a long miscue and put the Spaniard up a break once more at 4-3. Following a love hold for 5-3, Muguruza found a fabulous forehand in the next game to queue up double set point. Hsieh saved the first with a backhand winner, but double faulted on the second, ending the opening frame.

Hsieh then found herself down an early break in the second set, ceding a 3-1 lead to Muguruza after back-to-back double faults to end that game. However, that only kicked off a run of four consecutive service breaks, where both players used crosscourt winners to stay sturdy while returning serve.

Nevertheless, Muguruza still put herself in an excellent position to wrap up the match in two sets. The Spaniard blasted consecutive aces to hold for 6-5, and then held a match point in the very next game after a backhand error into the net by Hsieh. But Muguruza netted a forehand to erase her chance, and two points later, Hsieh fired a backhand winner to activate the tiebreak.

Hsieh opened the breaker with a backhand crosscourt winner, and from that point forward, the player from Chinese Taipei dominated the tiebreak, as Muguruza struggled with errors. Hsieh won nine straight points following Muguruza’s match point, giving her a 6-0 lead in the breaker and six set points. On the second set point for Hsieh, Muguruza sent a backhand long, and the match was tied at one set apiece.

Muguruza opened the decider by converting her second break point of the first game with a forehand return winner. Hsieh, though, used incredible defense to grasp four break points in the next game, finally leveling the set at 1-1 after finishing a rally with a forehand passing winner.

From there, Hsieh took control, as she found her targets with ease while Muguruza’s errors increased. Hsieh reeled off the final six games in the clash, having found her second wind following her narrow escape, and she breezed through the third set to ease into the second round of the Toray Pan Pacific Open for the very first time.