FLOWERY BRANCH, Ga. -- Atlanta Falcons rookie running back Tevin Coleman slipped in the shower at the team facility Wednesday and is going through the concussion protocol, coach Dan Quinn said Thursday.

Coleman, a third-round draft pick from Indiana, was the team's starting running back at the beginning of the season until he suffered a fractured rib in Week 2. Devonta Freeman then took over as the starter.

"[He] fell and hit his head, and he is in the concussion protocol," Quinn said. "That's unfortunate."

Coleman's availability for this week's game against undefeated Carolina is unclear. If he is unable to go, undrafted rookie Terron Ward would serve as Freeman's backup.

"He hasn't gotten a lot of opportunities, but he's done real good with the ones he's had," offensive coordinator Kyle Shanahan said of Coleman. "I was disappointed for him because I was hoping to use him a little bit more this week and stuff. And he's earned it. So I felt bad for him, but I've got a lot of confidence in Ward too. So, looking forward to [Ward] stepping it up for us."

Rookie running back Tevin Coleman, who opened the season as the team's starter, has 392 rushing yards on 87 carries this season. Dale Zanine/USA TODAY Sports

Coleman has 392 rushing yards on 87 carries with one touchdown. He also has caught two passes for 14 yards.

"You never want to see anybody go down like that, especially a guy who has been working his butt off and getting in his playbook to get back to the level he was playing at early in the season," fullback Patrick DiMarco said. "For that to happen, yes, it stinks. But I'm sure he'll recover quick and be back."

Freeman missed one game after suffering a concussion against the Indianapolis Colts.