After splitting the first two sets, the decider began with five successive breaks of serve as Kostyuk went into the sitdown with a 3-2 lead.
From that moment the 23-year-old put her foot to the metal to rattle through another three games and into the final four.
As she began to address the crowd, her emotions came to the surface and once she’d composed herself dedicated the victory to her country.
“I want to give this match to Ukrainian people and to their resilience,” Kostyuk said.
“I’m so happy to be through to the semifinals but I want to thank Elina for this incredible match.”
Kostyuk will be back on Thursday when she will meet No.8 seed Mirra Andreeva to vie for a spot in Saturday’s trophy showdown. One of them will reach a major final for the first time in their career.
More to follow…