Barbora Krejcikova came from behind to send Emma Raducanu crashing out of the Korea Open, winning 4-6, 7-6, 6-1 in Seoul.
Raducanu produced a gritty performance to claim the first set and was leading 5-2 in the second, but crumbled as Krejcikova fought back to force a tiebreak.
The British No1 came close to securing the win, but Krejcikova would not give in, saving three match points and ultimately taking the set.
The decider proved a grim procession with Raducanu’s spirit broken. Krejcikova dropped just one game en route to victory, and only required one match point to seal the deal - delivered with an uncompromising ace.
Raducanu left the stadium promptly as Krejcikova told the on-court interviewer: “A difficult, difficult match. I was very down, I don’t know how I turned it around.
“I am just happy to be here and happy to be tough in my head.”
Krejcikova will face top seed Iga Swiatek in the Korea Open quarter-final on Friday.
It will be a painful defeat for the Briton, who endured a frustrating third-round exit at the US Open in August, losing to Elena Rybakina, and had also struggled at this tournament. She appeared to be fighting back tears in the first set of her opening fixture against Jaqueline Cristian after struggling with her serve.
Raducanu had also chosen not to represent Great Britain at the Billie Jean King Cup, which is taking place concurrently.
She had come under fire from team captain Anne Keothavong for that decision, which she described as “disappointing”.
