MELBOURNE, Australia -- Hsieh Su-wei made it to the fourth round of the Australian Open for the second time in her career, as she eliminated No.26 seed Agnieszka Radwanska of Poland, 6-2, 7-5, in one hour and 40 minutes on Margaret Court Arena on Saturday night.

The player from Chinese Taipei, currently ranked World No.88, saw off her second consecutive seed, following her second-round upset of No.3 seed Garbiñe Muguruza. Hsieh enters the final 16 in Melbourne once more after her run to the second week as a qualifier in 2008.

"It’s amazing to be in the fourth round again," Hsieh told the press afterwards. "I tried to work a little bit harder last year, because I was injured on my ankle. I started working on my fitness and was doing very well. I think I will try to keep working hard this year."

Hsieh will face another well-known seed in her fourth-round tilt: No.21 seed and 2016 Australian Open champion Angelique Kerber of Germany, who disposed of 2008 Australian Open champion Maria Sharapova, 6-1, 6-3, earlier on Saturday night.

It was a scintillating display by Hsieh, who finished the match with 31 winners, and converted six of her eight break points. She deftly exhibited the all-court guile and grit which not only propelled her to a career-high singles ranking of World No.23 in 2013, but also to two Grand Slam doubles titles and the World No.1 ranking in that discipline in 2014.

"Everyone says [Radwanska and I] have a similar game, and it looks really similar," Hsieh said. "I tried to have a Plan A, Plan B for the match. But at the end, on the court, you just cannot think over your plan. So I just tried to focus on every point and every game."

"I tried to hit the ball a little bit bigger," Hsieh continued. "Her ball is a little bit different from the other girls, because she changes the rhythm a lot. She does slice, she does some faster balls and some slower balls. It’s really difficult if you get tight or you’re losing a little bit of concentration."

The first set was no contest, as Hsieh was whipping winners from the back of the court with ease, particularly off of her backhand. Radwanska was often flummoxed and sent out of position due to the inability to read Hsieh's shots, which are two-handed off both sides.

After an early exchange of breaks, Hsieh claimed another Radwanska service game when a stunning crosscourt backhand forced an error from the Polish athlete, to lead 3-1.

Hsieh did not face a break point for the rest of the set, and then broke Radwanska again to clinch the opening frame 6-2, when a beautiful angled forehand forced one more error from the 2012 Wimbledon runner-up. Hsieh had 16 winners to 13 unforced errors in the set, while Radwanska had five of each.

Radwanska had treatment on her leg between sets, and after she fell down an early break in the second set, Hsieh had all the momentum.

But successfully arguing a contested call seemed to light a fire under Radwanska, and by the middle of the set, she had gotten back on serve and was demonstrating her own well-renowned court craft, which brought her to the World No.2 ranking in 2012.

But Hsieh refused to cede her service after 4-4, and she finally got a crack at closing out the match as Radwanska was serving to stay alive down 5-6. A forehand by Hsieh forced an error from Radwanska after a long rally, giving the player from Chinese Taipei a match point.

But Hsieh hit a service return long, and Radwanska recovered to reach game point, attempting to send the match into a tiebreak. However, the Polish star double faulted, and then hit a forehand error wide to give Hsieh another match point. Hsieh took advantage the second time around, and skipped into the second week of the first Grand Slam event of 2018.

"At the winning moment, I was pretty excited, but now I’m pretty calm," Hsieh told the press. "When you’re still in the tournament...you need to be ready for the match. I have a doubles match tomorrow, and I still want to win in doubles. So I try to be calm, and then do all my stuff."

"I’m happy that every day I’ve been doing good, and my schedule, I’m handling good. That’s very good for me."