Three-time Madison world champion Amy Pieters is in an induced coma after surgery following a collision during training in Spain, Dutch Cycling said on Friday.
Pieters, 30, was transported to the hospital by air ambulance and doctors had to relieve pressure on her brain.
Dutch Cycling added that she would be in a coma for "the next few days" after which doctors would make an estimate on her recovery timeline.
Pieters won the Madison at the World Championships in 2019, 2020 and 2021 alongside Kirsten Wild but missed out on an Olympic medal in Tokyo this year after finishing fourth.