Former Rome champion Karolina Pliskova rallied from a set down and saved three match points to advance to the semi-finals of the Italian Open on Friday.
Pliskova, winner in 2019 and runner-up last year, battled past Latvia's Jelena Ostapenko 4-6, 7-5, 7-6 (7/1).
The ninth-seeded Czech will meet Croatia's Petra Martic for a place in the final.
Martic, ranked 25, ended the run of American Jessica Pegula 7-5, 6-4.
Pegula had dispatched number two seed Naomi Osaka of Japan on her way to her fourth quarter-final this season.
"Just proud, I think mostly, how I fought," said Pliskova, who saved three match points at 5-4 in the final set before storming back to victory after two hours and 20 minutes.
"It was definitely a horrible start for me. I'm just happy that I stayed in there and fought till the end."
It was the second clay-court win for Pliskova over Ostapenko, having come from a set down against the Latvian in Stuttgart last month.
Each player broke serve seven times, but Ostapenko paid heavily for 14 more unforced errors than her Czech rival.
Results from the ATP/WTA Italian Open in Rome on Friday (x denotes seeding):
Men
Quarter-finals
Rafael Nadal (ESP x2) bt Alexander Zverev (GER x6) 6-3, 6-4
Reilly Opelka (USA) bt Federico Delbonis (ARG) 7-5, 7-6 (7/2)
Women
Quarter-finals
Karolina Pliskova (CZE x9) bt Jelena Ostapenko (LAT) 4-6, 7-5, 7-6 (7/1)
Petra Martic (CRO) bt Jessica Pegula (USA) 7-5, 6-4