SEOUL, South Korea - Richel Hogenkamp made it into her first WTA quarterfinal in over four years - and her first on hardcourts, with a 6-4, 6-4 win over Denisa Allertova at the KEB Hana Bank-Incheon Airport Korea Open.

"She plays very flat, so I tried to mix it up, give her some higher balls and some slice," Hogenkamp said after the match. "She likes a strike zone at about hip level, so by mixing it up, I was able to get her to make some more mistakes. I think it was a good tactic."

Playing the first match on Wednesday's Centre Court schedule a day after knocking out countrywoman and No.2 seed Kiki Bertens, the 25-year-old Dutchwoman broke serve four times to beat the big-hitting Czech after 75 minutes.

"Yesterday was a very tough match, so I obviously needed time to recover, eat well, and do what I had to do," she explained. "Today I felt good and I’m ready to play some doubles this afternoon."

Hogenkamp last made the final eight of a WTA tournament at the Ericsson Open back in 2013, but strong results on the ITF Circuit - and a maiden main draw win at Roland Garros - helped her earn a career-high ranking of No.94 this summer. Just outside the Top 100 heading into the Asian Swing, she aims to get back into direct contention for the Australian Open main draw in 2018.

"I worked on my groundstrokes a lot at the beginning of the year. On hardcourts, it’s important to have good timing and use the speed of the opponent. I think that worked out well today."

Standing between Hogenkamp and a first-ever WTA semifinal will be wither Arantxa Rus or Priscilla Hon.

Over on Court 2, Luksika Kumkhum ended a WTA quarterfinal drought of her own; the 24-year-old Thai qualifier won a fourth straight match in Seoul with a 6-3, 6-3 win over Ekaterina Alexandrova. Most famous for her stunning upset over Petra Kvitova at the 2014 Australian Open, Kumkhum is into her first quarterfinal since that year, when she went on to reach the semifinals in Osaka. 

Kumkhum will next play No.4 seed Sorana Cirstea or surging American Nicole Gibbs for a spot in the final four.

Elsewhere, Sara Sorribes Tormo of Spain beat Han Na-Lae 6-1, 6-2, Kristie Ahn of the USA beat Tatjana Maria in a close-fought match, 7-5, 7-5, while 21-year-old Beatriz Haddad Maia of Brazil beat Irina-Camelia Begu 6-3, 4-6, 6-2.