Why K.J. Costello, not Justin Herbert, is the Pac-12's best QB

The stage is set for Oregon quarterback Justin Herbert to potentially be the No. 1 QB drafted next April, as the senior signal-caller has set the tone for the Ducks the past few years. Still, there's a quarterback in the Pac-12 who has all the tools to be better than Herbert once the season is over.

That man is Stanford's K.J. Costello.

As the days until opening weekend dwindle, the season's worth of data from 2018 has become increasingly less important. Still, utilizing the Pro Football Focus grades from last year and even further back, the numbers suggest Hebert's best college football might be behind him while the top of Costello's game could be still to come.

It is important to note this is not a draft-eligible look ahead at these two players but rather is a look back at what they've done, where they've been and what they can be as college quarterbacks for the 2019 season.