Romanian top-seed Simona Halep came from a set down to defeat Barbora Krejcikova 3-6 7-5 6-2 and reach the quarter-finals of the Prague Open.

Trailing 2-0 in the final set, Halep replied by winning six consecutive games, converting her first match point when the 118th-ranked Krejcikova double-faulted.

“She played great and it was really tough to find my rhythm,” Halep said.

“I just stayed focused for every ball I played.”

World No.2 Halep needed six set points in the second set to level the match, having lost her serve six times up to that point.

She double-faulted 10 times in the match.

“My serve is not great at this point but I keep working on it,” Halep said.

“Hopefully, it’s going to get better day by day.”

Halep took a medical time-out after the second set for her right shoulder and needed more treatment in the final set.

“Then, I could serve a little bit stronger, so I needed that and I’m happy that it worked,” she said.

Halep next faces lucky loser Magdalena Frech after the 174th-ranked Pole defeated Arantxa Rus 6-3 2-6 6-4 to make her first career quarter-final.

Wild-card entry Eugenie Bouchard advanced by overcoming Tamara Zidansek 7-6 (7-2), 6-7 (7-2), 6-2 to reach her second quarter-final this year.

The former world No.5 wasted a 4-1 lead in the second set before prevailing in the decider after almost three hours to set up a quarter-final against third-seeded Belgian Elise Mertens.

The Prague Open is the second European tournament since the WTA restarted amid the coronavirus pandemic, with strict health protocols in place.