During his junior season, he threw for 2,835 yards, 41 touchdowns and five interceptions, leading Trinity Catholic to the Florida Class 2B state title.

Brantley finished his high school career with an FHSAA record 99 touchdown passes, breaking the previous state mark of 98, held by Tim Tebow.

Brantley first saw playing time in the season opener against Hawaii, and would go in as the backup after the starters were pulled in several conference games.

Brantley earned media attention during the 2009 season after starting quarterback Tim Tebow suffered a concussion in a September 26 game against Kentucky.

It was speculated Brantley would make the first start of his Gator career in Baton Rouge at LSU, but Tebow was cleared to play on the day of the game.