Britain's Stefan Wilson, younger brother of the late F1 and IndyCar driver Justin, will miss Sunday's Indianapolis 500 after injuring his back in a heavy crash on Monday.
Wilson went into the barrier after his car was hit from behind in afternoon practice at the Indianapolis Motor Speedway by compatriot Katherine Legge.
The 33-year-old's Dreyer & Reinbold team said he had suffered a fracture of the 12th thoracic vertebrae.
"Based on this type of injury, Wilson will not be allowed to compete in this Sunday's 107th Indianapolis 500 Mile Race," the team added.
Wilson would have been starting his fifth Indianapolis 500. His brother made eight appearances but died after being hit on the helmet by debris in an IndyCar race at Pocono Raceway in 2015.