Mark Cavendish has dropped out of the Great Britain World Championships only hours after being named to the team. His place in the road race is expected to be taken by Geraint Thomas.
Cavendish, 23, has had 17 wins this season, including most recently three stage wins in the Tour of Missouri. He was selected by British Cycling to race the Worlds road race, but shortly after the announcement, his name was taken off the list again with the mention that he "withdrew".
"Mark has had a long season," explained Kristy Scrymgeour, Team Columbia spokeswoman. "He is mentally tired and feels that he doesn't have the form to compete at the top level at World Championships next week."
The men's road team will now have David Millar, Chris Froome, Steve Cummings, Russell Downing, and Ian Stannard, with Geraint Thomas still to be confirmed. Millar and Cummings will also ride the time trial.
Olympic Champion Nicole Cooke will lead the women's team. She will be supported by Sharon Laws, Emma Pooley, Lizzie Armitstead, and Jess Allen. Law and Pooley will ride the time trial.
For the U-23 team, Ben Swift, Peter Kennaugh, Alex Dowsett, Jonny Bellis and Jonny McEvoy will ride the road race, with Dowsett and Russel Hampton in the time trial.