ATLANTA (AP) — San Francisco 49ers star Christian McCaffrey left the game Sunday against the Atlanta Falcons with a hip injury but was able to return in the second half.

McCaffrey was hurt after giving the unbeaten Niners an early lead with a 1-yard touchdown leap on fourth down to cap their opening possession.

The three-time All-Pro running back was checked out in the injury tent, then came back out to do some running on the sideline with his helmet on. He didn’t return in the first half, however, jogging to the locker room before the break.

McCaffrey returned to the field for San Francisco's first possession of the second half, with the 49ers trailing 19-14. He was dropped for a 2-yard loss on his first carry.

McCaffrey was a big contributor on San Francisco's first drive with two catches for 40 yards and four carries for 29 yards. It wasn't immediately clear how he was injured, but he went out after catching a 5-yard pass from Brock Purdy to begin the 49ers' second possession.

San Francisco, which came into the game at 6-0, has dealt with a rash injuries over the past several seasons. They faced the Falcons without their two top receivers as Mike Evans (Achilles/rib) and Deebo Samuel Sr. (hamstring) were both ruled out.

With McCaffrey on the sideline, Kaelon Black took over as the lead running back. He had a 30-yard touchdown run that pushed San Francisco's lead to 14-3, but also lost a crucial fumble at the Atlanta 29 with the 49ers in position to add more points.