A dramatic crash ended Jason Kenny's bid to win the gold medal in the keirin at the Track World Cup in Glasgow.
The triple Olympic gold medallist fell in the closing stages of the final after clipping the wheel of Germany's Stefan Boetticher.
French rider Quentin Lafargue collided with Kenny, with Boetticher going on to take the gold medal.
Kenny has withdrawn from Sunday's individual sprint, along with Welsh rider Lewis Oliva, who also crashed.
Sprint coach Iain Dyer said: "Jason is feeling very sore after his crash yesterday and didn't get much sleep last night. Having consulted with the team doctor, Jason has decided to withdraw from today's competition."
Oliva, who is riding for the Welsh trade team Team USN, will have an X-ray on his hand.
Kenny, 24, suffered bruising and remounted his bike after receiving treatment on the track.
Dyer told BBC Sport: "He was looking down and checking to see where Lafargue was as he knew he was close.
"The next thing he said he could smell the rubber burning with his front tyre and Boetticher's back tyre, and that's when he realised he was coming down. He didn't even see it coming."
The Bolton rider won the silver medal alongside Ed Clancy and Philip Hindes in the team sprint on Friday.