Smith's (neck) contract with the Lions' practice squad expired Monday, per the NFL's transaction log.
Smith sustained an apparently significant neck injury when he was elevated for the Week 5 loss to New England. He then entered the concussion protocol before being placed on the practice-squad injured list with a neck designation Oct. 19, and he was never removed from this list before the expiration of his deal. Smith has now appeared in 10 regular-season games while spending time with Dallas, San Francisco and Detroit over the past three seasons.