Race leader Annemiek van Vleuten has been ruled out of the rest of the Giro Rosa and will not defend her world title after breaking her wrist.
The 37-year-old fell in the last 500 metres of stage seven on Thursday alongside Mitchelton-Scott team-mate Amanda Spratt of Australia and Dutch compatriot Marianne Vos.
All three riders finished the stage but Spratt, who has concussion, and Van Vleuten are now both out of the race.
“I knew straight away,” she said.
“I’m super sad it’s not possible to defend the maglia rosa, but even more, no worlds on a course that suits me. I’m disappointed that I cannot defend my world champion’s jersey.”
Van Vleuten, who will return to her native Holland for surgery in the coming days, had been due to defend her world title at next week’s Road World Championships in Imola.
The stage was won by Belgium’s Lotte Kopecky, with Britain’s Lizzie Deignan second and Kasia Niewiadoma in third.
Two-time winner Van Vleuten led Poland’s Niewiadoma by one minute 48 seconds overall, with Anna van der Breggen five seconds further back.
Friday’s stage eight of the Giro Rosa is a hilly 91.5km course from Castelnuovo della Daunia to San Marco la Catola.