Raiders quarterback Jimmy Garoppolo has been placed in the NFL’s concussion protocol following Sunday night’s 23–18 loss to the Steelers, Las Vegas coach Josh McDaniels said Monday.

Even though Garoppolo played the entire game against Pittsburgh, he missed his postgame media availability while he was undergoing medical evaluation. The 31-year-old must be fully cleared before he can return to action. The Raiders’ next game is scheduled for 4:05 p.m. ET at the Chargers.

It’s unknown at this time whether a specific play caused the injury to Garoppolo. He was sacked four times by the Steelers.

In three starts for the Raiders (1–2), Garoppolo has completed 68.1% of his pass attempts for a total of 709 yards with five touchdown passes and six interceptions. Veteran Brian Hoyer and rookie Aidan O’Connell are the other two quarterbacks on the Las Vegas roster. Hoyer is in his first season with the Raiders, but he previously played for McDaniels with the Patriots.