Joe Milton banged his thumb on a helmet but is expected to be OK

Cowboys backup quarterback Joe Milton left the joint practice with the Rams after hitting his hand on a helmet.

The Cowboys called it precautionary.

Coach Brian Schottenheimer said Milton could have finished the scrimmage after injuring his thumb. Milton, though, will undergo additional testing to confirm he indeed is fine.

"[The medical staff] feels really good about it," Schottenheimer said, via Jon Machota of TheAthletic.com.

Will Grier replaced Milton with the second team.

Milton, who was acquired in an offseason trade with the Patriots, is expected to start Saturday's preseason game against the Rams.