Updated

Mike Riley, the dean of the Pac-12's coaches embarking on his 14th season at Oregon State, is always unapologetically optimistic each season.

This season is no different — but a big reason behind his hope is returning quarterback Sean Mannion, who decided to stick with the Beavers for a final season.

Mannion embodies Riley's pro-style offense. The 6-foot-5 senior set a Pac-12 season record last year for yards passing with 4,662 and threw an Oregon State-record 37 touchdown passes, third-most for a single season in conference history.

The fifth-year senior has collected 10,436 career yards passing and could break Matt Barkley's record of 12,274 before the end of the season.