Steve Cummings suffered a broken elbow in a crash towards the end of the opening stage of the Tour of Belgium.
The 33-year-old Briton, who has been with BMC Racing since leaving Team Sky in 2011, crashed with around 20km remaining of the ride from Lochristi to Buggenhout.
Cummings was disposing of a drinks bottle when he suddenly lost control and tumbled on to the pavement, hitting the ground hard.
Although he was able to complete the stage more than 17 minutes behind winner Tom Boonen, team doctor Dario Spinelli said X-rays confirmed a small fracture.
Cummings, who won the Tour Mediterraneen and finished second at the Tour of Dubai, also suffered bruising to his left hip.
“As I threw the bottle, my front wheel hit a hole and threw me off balance and then I just fell,” said Cummings, who faces a spell out of action because of his injuries. “It was a bit weird.
“I was looking forward to this race and other races, so I am really disappointed.”