The Texans officially signed Mack to their practice squad Wednesday.
Mack was among Houston's roster cuts Tuesday, but now that he's back with the organization in some capacity, he'll be eligible for elevation to the active roster Week 1 and beyond. With rookie fourth-round pick Dameon Pierce poised to lead the backfield, Mack would be vying for snaps with Rex Burkhead and Dare Ogunbowale for any games in which he's active.