Colombian rider Juan Mauricio Soler has been placed in an artificial coma at a hospital in St Gallen, a day after a serious crash in the Tour de Suisse.
The 28-year-old athlete suffered from bleeding in the brain as well as "multiple fractures".
Several spectators were also hurt in the accident. The race was stopped midway through Thursday's stage to allow doctors to treat the injured but resumed minutes later.
Until the crash, Soler had been holding onto second place overall and was less than a minute behind leader Damiano Cunego of Italy.
At the end of the sixth stage, Cunego retained his place by coming third. Steven Kruijswijk of the Netherlands won the sixth stage of the race, a 157km ride from Tägerschen in Switzerland to Malbun in Liechtenstein.
The Tour de Suisse is taking place for the 75th time in 2011.
swissinfo.ch and agencies