SEOUL, South Korea - Varvara Lepchenko continued her assault towards the Top 20 at the KDB Korea Open on Thursday afternoon, beating Anabel Medina Garrigues to reach her fourth WTA quarterfinal of a breakthrough year.

Once the No.6-seeded Lepchenko tucked away the 43-minute first set she really started opening her shoulders and unleashing her heavy forehand, reeling off the first four games of the second set and closing the match out, 64 61.

Before this year, World No.21 Lepchenko only had one WTA quarterfinal to her name - Ponte Vedra Beach in 2010. She has reached four this year alone, at Memphis, Madrid, Carlsbad and now Seoul. She is 0-4 in her first four WTA quarterfinals though, so she could break some new ground this week.

Next for Lepchenko is Tamira Paszek, who won 11 games in a row from 1-2 in the first set to dismiss Korean wildcard Lee So-Ra in 50 minutes, 62 60.

Paszek leads Lepchenko in their head-to-head series, 2-1.

No.1 seed Caroline Wozniacki and No.7 seed Klara Zakopalova also set up a quarterfinal clash, after Zakopalova rallied from 5-3 down in the second set and saved set point in the tie-break of a 61 76(6) win over Magdalena Rybarikova, and Wozniacki cruised past French qualifier Caroline Garcia, 62 63.

Zakopalova has an impressive 10-3 career record at this tournament, her best showing being a runner-up finish in 2010 (to Alisa Kleybanova).

"I just love coming back here," Zakopalova said. "The people here are so nice and I have many fans here. I don't know why - maybe it's because I've played well here. The hardcourts here are great and I love playing on them."

The Czech veteran is actually playing as well as ever right now, currently sitting at a career-high No.27 in the world - what's the secret of her longevity?

"There's no secret - I've been with my coach for three years and we work well together, and the hard work is paying off," she said. "I've been playing a long time, but I'm still enjoying it all and I'm still fit. I haven't had any injuries, which is lucky. I'm enjoying my life right now and I hope to play as long as I can!"

Wozniacki leads Zakopalova in their head-to-head series, 2-0.

"She's a great player - she was No.1 in the world," Zakopalova said of the former World No.1. "I have to be patient - she doesn't make any mistakes and runs a lot. But I have nothing to lose. I just want to play 100%, just give it my best."

The other quarterfinal set Thursday is an all-lefty battle pitting No.8 seed Ekaterina Makarova against María José Martínez Sánchez, after Makarova beat American qualifier Jamie Hampton, 63 75, and Martínez Sánchez beat No.4 seed Nadia Petrova by walkover due to a low back injury.

Makarova leads Martínez Sánchez in their head-to-head series, 3-0.

The other KDB Korea Open quarterfinal between No.3 seed Kaia Kanepi and Kiki Bertens was set on Wednesday and will be a first-time meeting.