According to Trevor Sikkema of Pro Football Focus, Arians addressed the possibility of Leftwich leaving this past Monday. Arians said that if Leftwich takes a job elsewhere, he will call offensive plays himself in 2022.
The Tampa Bay Buccaneers head coach is no stranger to offensive play calling. It was Arians' primary job for the better part of 30 years before he got his first NFL head coaching job with the Arizona Cardinals in 2013.
That might not preclude Arians from hiring or promoting someone to replace Leftwich in the role of offensive coordinator. But there have been plenty of coaches who have had no trouble at all calling the plays on their specific side of the ball.
It's hard to tell how much of the Bucs' success on offense over the past three years has been solely on Byron Leftwich. When he took over as offensive coordinator in 2019, Jameis Winston was already a fairly decent quarterback.
But under Leftwich's leadership, Winston had his best season ever (even if he did lead the NFL in turnovers). And when Tom Brady entered the fold in 2020, the Bucs' offense was supercharged.
Even then though, Brady was already an established quarterback.
It will be very interesting to see how the Buccaneers offense looks in 2022 if Arians is calling the shots on offense.