WATCH: Mariota's first NFL interception goes 69 yards for a TD

Tennessee quarterback Marcus Mariota threw the first interception of his young NFL career in the Titans' Week 3 game against the Indianapolis Colts on Sunday, and if the early results are any indication, his tackling needs some work.

In the second quarter, Colts safety Dwight Lowery intercepted a deflected Mariota pass intended for Tennessee tight end Delanie Walker. Lowery grabbed the ball and returned it 69 yards for touchdown. The pick six gave Indianapolis a 14-0 lead.

Though the play was ruled an interception, it appears Walker may have had possession before fumbling. Whether Mariota was to blame for the turnover is up for debate. His defensive prowess, however, is not.

The Heisman Trophy winner attempted to make a play toward the sideline to prevent the touchdown but fell victim to a juke from Lowery and tumbled out of bounds.

It's safe bet Mariota's teammates will let him hear about it Monday when they look at the film.