Baker Mayfield wasn't supposed to be a star player. He wasn't heavily recruited and even had to walk on at Texas Tech. Once there, Mayfield ended up playing just one season before losing his job to Patrick Mahomes.
He then enrolled at Oklahoma and again had to walk on to the program. This time, he was able to keep the job and wound up having a great career for the Sooners which culminated in him winning the Heisman trophy in 2017.
That year, he had 4,627 yards passing with 43 touchdowns against only six picks.