Mack had four carries for 11 yards and two receptions for 20 yards, but was part of a key fumble near his own end zone in Sunday's loss to Tennessee. Quarterback Jacoby Brissett was charged with the fumble on a pitch, but Mack had it in his hands and dropped the ball.
Mack played just 19 snaps and didn't get a target or carry after his key third-quarter fumble. It's possible he may lose playing time next week due to the fumble, but the Colts would be better served to give him experience ahead of 2018. Besides, Mack hasn't had previous issues with ball security.