Quarterback power rankings: Best college football quarterbacks of 2019

SANTA CLARA, CA - JANUARY 07: Trevor Lawrence #16 of the Clemson Tigers throws a touchdown against the Alabama Crimson Tide during the College Football Playoff National Championship held at Levi's Stadium on January 7, 2019 in Santa Clara, California. The Clemson Tigers defeated the Alabama Crimson Tide 44-16. (Photo by Jamie Schwaberow/Getty Images) /

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PALO ALTO, CA – SEPTEMBER 08: K.J. Costello #3 of the Stanford Cardinal drops back to pass against the USC Trojans in the second quarter of an NCAA football game at Stanford Stadium on September 8, 2018 in Palo Alto, California. (Photo by Thearon W. Henderson/Getty Images) /

6. K.J. Costello, Stanford

With 2018’s display, Stanford has its best quarterback since Andrew Luck left for the NFL in 2012.

K.J. Costello found the full-time starting role in Palo Alto as a junior and took off with it from the first game. With 332 yards and four touchdowns, it put him on the radar and continued into conference play, with another 327 yards and three touchdowns in a win over Oregon.

A midseason slump deterred Costello and the Cardinal, however. They lost four out of five games, and the star quarterback had six interceptions in this stretch.

After a November win over Oregon State, though, Costello led the program back to prominence with nine combined passing touchdowns over two games for 342 and 344 yards, respectively.

The highs were great for Costello, and the lows showed his inconsistency. Stanford will hope for a full season of him playing like one of the nation’s top quarterbacks because he has the potential to rank higher than the middle of the top 10.

Plus, it will be a season to watch for his draft status. 6-foot-5 quarterbacks with arm talent usually hear their name called by an NFL team in April. Another good year could take him into the first or second day of the draft.