It extended the 23-year-old’s unbeaten streak on clay to 12 matches following titles in Roeun and her maiden WTA 1000 trophy in Madrid earlier this month.
Despite stumbling when serving for both sets, the Ukrainian maintained control throughout to set a second-round meeting with Katie Volynets or Clara Burel on the back of 20 winners, including 12 off the forehand.
Afterwards during her on-court interview, Kostyuk revealed it had been an emotional build-up to the match following news from her parents.
“I'm incredibly proud of myself today,” Kostyuk said after the handshake.
“I think it was one of the most difficult matches of my career. This morning, 100 metres away from my parents' house [in Ukraine], a missile destroyed the building.
“It was a very difficult morning for me. I didn't know how this match was going to turn around for me. I didn't know how I would handle it.”
More to come …