Chargers quarterback Justin Herbert is out due to a right ankle injury sustained in the game against the Steelers.

PITTSBURGH (AP) — Los Angeles Chargers quarterback Justin Herbert left Sunday’s game against the Pittsburgh Steelers with an ankle injury and was questionable to return.

Herbert was replaced by Taylor Heinicke.

Herbert spent most of the week rehabbing a right ankle injury he initially injured last week in a win over Carolina. He started anyway and played well, completing 12 of 18 passes for 105 yards and a touchdown before getting sacked by Pittsburgh’s Elandon Roberts midway through the third quarter. He stayed in for one more play before heading to the sideline.

The Chargers were careful with their franchise quarterback after his ankle was rolled up on in the third quarter last week against the Panthers. He stayed in to finish off the 26-3 rout but did not practice on Wednesday and was listed as limited on Thursday after doing some light throwing.

Herbert went through a typical warmup on the Acrisure Field turf about two hours before kickoff and was given the OK to play.

The Chargers lost outside linebacker Joey Bosa to a hip injury in the first quarter. Bosa, who has been dealing with the injury for some time, got up slowly at the end of Pittsburgh’s first drive and did not return.