Raducanu, who crashed out of the US Open in the first round last month, overcame a sluggish start and a late wobble to win 6-3, 7-5 in Seoul.

The Briton, the sixth seed in the tournement, will face third seed Magda Linette (30) of Poland next.

"I think that serving big and serving well and a lot of aces, especially in the second set, helped me get off to a pretty good lead, 4-1 up, which gave me bit of a cushion because Yanina started fighting back and it was a competitive second set," said Raducanu.

Eyeing up Linette in the last eight, the former US Open champion added: "Linette is a challenging opponent with many years more experience than me. I'm focused on that match and not thinking further ahead."

Raducanu reached a career-high 10th in the world in July, but is now 77th, having failed to build on her shock success at Flushing Meadows last year.

Wickmayer held her own initially, exchanging breaks to 3-3, before the Briton picked up the pace to take the first set.

Raducanu carried that momentum into the second set and was leading 4-1, only for Wickmayer to fight back to 4-4.

Raducanu eventually pulled through, breaking Wickmayer's serve on the way to clinching the set and match and later told reporters that she fed off the adoring Korean fans. 

"I think that their support for me was really nice and I really appreciate it. I feel so welcome and really comfortable on the court here."