When Aaron Rodgers sat behind the retirement-challenged Brett Favre, he was on the bench for three seasons, then went 6-10 his first year as a starter, before having an 11-5 season.
Rodgers has commented several times that his stint behind Favre did him immense good, since he had a chance to learn the NFL game, get used to the NFL speed and build his body into an NFL quarterback before starting.
He’s gone on to win nearly every award a QB can achieve.
Matt Cassel hadn’t started a game since high school when he was drafted in the seventh round by the New England Patriots.