ATLANTA — Justin Fields will start at quarterback for the Pittsburgh Steelers in Sunday’s season opener against the Atlanta Falcons, while Russell Wilson will be sidelined with a calf injury.

Wilson, who was limited in Thursday and Friday practices after aggravating the injury first sustained in training camp, will be the Steelers’ emergency quarterback — meaning he can only play if there are injuries to Fields and Kyle Allen, who will serve as the backup Sunday.

Wilson took the field just before 10:30 a.m. ET Sunday and went through a series of throws for about 15 minutes with a pair of Steelers equipment staffers. Wilson appeared to move slowly through the warmup as he took several small dropbacks before firing off a pass. He warmed up in each end zone, finishing with fades to the corner.

Wilson then returned to the field just after 11 a.m. ET and chatted briefly with general manager Omar Khan. Wilson then resumed throwing, this time to quarterbacks coach Tom Arth. Fields warmed up nearby, throwing the ball with tight end Connor Heyward and wide receiver Calvin Austin III. Wilson still moved minimally through warm-ups, while Fields repped rollouts and dropbacks.

Both Wilson and Fields threw passes to wide receivers as they lined up for routes during warm-ups, but Fields took the first reps of the drill each time, followed by Allen and then Wilson.

Fields started 38 games in his three-year tenure with the Chicago Bears before being traded to the Steelers for a conditional 2025 sixth-round pick in the offseason. The sixth-round pick becomes a fourth if Fields plays more than 50% of the team’s snaps this season.