Wickmayer - the only seed to make it through to the quarterfinals, at No.2 - continued her path of destruction through the draw, storming past Zheng Saisai in an hour and 17 minutes, 63 61. Though her Chinese opponent bombed seven aces during the match, Wickmayer broke serve five times, and was strong on her own serve - she held seven of eight service games, losing it once second set.
"She was a tough opponent," Wickmayer said of Zheng. "She's a great doubles player, which was a bit of a change for me, but I knew what I had to do today, and I'm excited about my match tomorrow."
Wickmayer and Kumkhum will be playing against each other for the first time.
The other two quarterfinal matches were both grinders, starting with Dinah Pfizenmaier's 36 63 62 win over Katarzyna Piter, and then Alison Van Uytvanck's two-hour, eight-minute, 63 67(2) 75 victory over Russian qualifier Ekaterina Bychkova. Van Uytvanck was just two points from losing the match in the third set, finding herself serving 4-5, 15-30 in that decider - but she pulled it through in the end.
"It's my first time at this tournament in Taipei and I'm really enjoying it," Van Uytvanck said. "It's a really well organized tournament and Taipei Arena is really beautiful, and the hotel is very nice as well.
"Bychkova was serving really well and it was tough to break her. I had a match point in the second set and couldn't take it, and the third set was really tough, but I was able to win it, so I'm very happy."
The big-serving theme continued in those last two quarterfinals as well - both Pfizenmaier and Van Uytvanck dropped 10 aces in their matches, but the biggest serving of the day actually went to one of the vanquished ones - Bychkova, who is perhaps best known for her first round stunner over defending champion Svetlana Kuznetsova at the 2005 US Open, blasted a whopping 14 aces during her defeat.
Pfizenmaier and Van Uytvanck have played each other once before, with Pfizenmaier winning in straight sets, 64 64 - it was also on indoor hardcourts, in the final of an ITF Circuit event last year.
The semifinals will take place on Saturday and the championship match will take place on Sunday.