Mack lost three yards on six carries and had one reception for 11 yards in Sunday's loss to Arizona.
Mack played just 11 snaps on offense compared to 28 for Robert Turbin behind Frank Gore in a reversal from Week 1. It's likely the Colts liked using Turbin in pass protection. Mack may have more upside if Gore were to get hurt, but it looks like he'll have a limited role on offense when his Week 1 usage suggested a larger role.