What other team did the Baker Mayfield play for before taking Trevor Knight's position?
Baker Mayfield:  Mayfield began his college football career as a walk-on player for the Texas Tech Red Raiders. Trevor Knight:  After leading Oklahoma to an 8–5 record in the 2014 season, he lost the starting job in an open quarterback competition to Texas Tech transfer Baker Mayfield prior to the 2015 season.
i don't know