Florida quarterback Will Grier is suspended for at least the remainder of the 2015 season for violating the NCAA's substance abuse policy, head coach Jim McElwain announced Monday.

The school intends to appeal the decision, which carries an automatic one-year suspension from the NCAA. That means Grier would miss the first six games of the 2016 season.

McElwain said Grier took an over-the-counter supplement, and something in the medication tested positive for performance-enhancing drugs. The medication was not approved by Florida trainers, according to ESPN's Brett McMurphy.

Grier reportedly took a supplement called Ligandrol, according to ESPN, which isn't classified as a steroid, but is still banned.

Grier wasn't expected to play against Ole Miss on Oct. 3, after coming down with the flu. Instead, he played through it, throwing for 271 yards and four touchdowns in the 38-10 upset.

Florida, at 6-0, has been one of the nation's most surprising schools. The Gators are set to take on undefeated LSU on Saturday in a top-10 matchup.

This season, Grier broke onto the scene in a big way, throwing for 1,204 yards and 10 touchdowns. He has also rushed for 116 yards with two scores.

Backup Treon Harris will take over starting duties.

Harris hasn't seen much game action since losing the starting job to Grier. This season, he's thrown for 269 yards and two touchdowns in two appearances.