FLOWERY BRANCH, Ga. — Despite naming Tua Tagovailoa the team's starting quarterback for Week 1 of the 2026 season, the veteran quarterback will not play Sunday against the Pittsburgh Steelers. Tagovailoa has officially been ruled out of the game with an oblique injury.

Cooper Rush will make the start at quarterback. Jack Strand will act as Rush's backup.

"Cooper has been a backup in this league," head coach Kevin Stefanski said Friday. "He knows how to prepare,"

Stefanski confirmed there was not a consideration or possibility of Michael Penix Jr. being active Sunday. The head coach said earlier this week the plan was to keep Penix inactive this weekend. Penix told the media Monday in open locker room that he is not quite back to 100% yet.

"Mike will be ready when he is ready," Stefanski said. "... I trust in this process and I trust in what we are doing medically and I trust Mike."

Tagovailoa was first placed on the team's Thursday injury report with an oblique injury. It was observed during the open period of Thursday's practice that Tagovailoa touched his back before sitting down on the field briefly during individual drills.

Rush took all of the first-team reps with the offense thereafter.

Speaking to the media Thursday afternoon, Rush said the reps he was able to get with the first-team offense were really important.

"It's huge," Rush said. "All those reps matter, and its a big advantage for me. If you have to go in there, at least you have some reps."

Stefanski said Tagovailoa's oblique injury is not related to the back injury the quarterback had at the start of training camp in July.

"I am disappointed for him, obviously," Stefanski said of Tagovailoa. "He's a very competitive person. So, we're disappointed. But he's going to rally behind Coop and do everything he can to help Cooper."

Stefanski did not specify how long Tagovailoa would be unavailable. When asked if it was "day-to-day" or "week-to-week" the head coach said, "yes."

Rush joined the team in late July when training camp began, meaning he missed much of the spring calendar's install of the offense. Still, Rush said Thursday that the coaching staff has done a good job catching him up to speed. He noted that it helps that everyone is in the first year of Stefanski and offensive coordinator Tommy Rees' scheme.

Stefanski agreed with Rush's assessment.

"Year 1 of any system, for coaches and players, you get to know where the bones are buried on all these plays," Stefanski explained. "You spend more time talking about the 'why,' and the intent of the play. Some times you get to Year 2 and 3 and everybody kind of breezes past that. So, I do think there is an advantage to the guys in that room all asking really good questions so we can all figuratively get on the same page."

Through three games with Atlanta this preseason, Rush completed 30 of his 48 pass attempts for 254 yards. He had a touchdown and 2 interceptions.

Over his career, Rush has started 16 games, completing 61.1% of his attempts for 3,766 yards with 20 touchdowns and 14 interceptions through eight years.

The Falcons — with Rush as their starter — will travel up to Pittsburgh this weekend to face the Steelers in Week 1. Kickoff is scheduled for 1 p.m. ET.