Madrid Open winner and world No 1 Aryna Sabalenka was sent packing in the quarterfinals by Chinese eighth-seed Zheng Qinwen 6-4, 6-3.
Sabalenka's stunning clay-court form deserted her as she fell in straight sets to Olympic gold medallist Zheng.
It was seventh time lucky for the world No 8 as she at last got the better of her Belarusian opponent with a confident display under the lights in Rome.
After surviving early pressure on her own serve, Zheng broke Sabalenka to take a 3-2 lead in the first set before serving out.
Zheng then pounced in Sabalenka's first service game in the second frame to go up a break.
Sabalenka showed determination to make gritty holds in the fifth and seventh games of the set, but she could not make inroads on Zheng's service as the 22-year-old powered into the semis.
She's certified gold 😉
— wta (@WTA) May 14, 2025
Zheng Qinwen never let up, delivering a masterclass performance as she powered past Sabalenka 6-4, 6-3!#IBI25 pic.twitter.com/EgCcY6mHV0
"It's been a long time I haven't arrived in semifinals," Zheng told Sky Sports after securing her first semifinal appearance of the season.
"It was not easy for me because at the beginning of the year I got some struggle with my arm.
"So right now I'm just perfectly in shape and trying to play better tennis all the time."
Zheng will meet Coco Gauff in the last four after the American earlier beat Mirra Andreeva 6-4, 7-6 (7/5).
Gauff has guaranteed herself No 2 in the women's world rankings with her solid displays in Rome, where she saw off seventh seed Andreeva.
Former US Open winner Gauff said that she had "a lot of confidence" for the last four, where she will face an opponent against whom she holds a 2-0 record.
Gauff, 21, is looking for her first title of the season ahead of Roland Garros, after losing the Madrid final to Sabalenka.
Indian Wells champion Andreeva, at 18 years old the youngest woman to reach the last eight at the Foro Italico since Gauff in 2021, put up surprisingly little resistance in a low-key first set.
And Gauff had too much for her in the second, quickly responding to each of Andreeva's breaks of serve before coming through a tricky tie-break.
Coco into a THIRD Rome semifinal 💫
— wta (@WTA) May 14, 2025
The fourth seed sees off Mirra Andreeva 6-4, 7-6(5) to book her spot in the final four in the Italian capital.@CocoGauff | #IBI25 pic.twitter.com/kFpwrljKot