Gray wound up clearing waivers today, which led to speculation that he could return to the Patriots, who lost Dion Lewis for the season.
Gray, 25, was waived by the Patriots this last weekend, as they cut their roster down to 53 players. The Dolphins wound up signing him to a contract back in September before promoting him to their active roster soon after.
Miami waived Gray earlier in the week to make room for C Sam Brenner.
This season, Gray has appeared in six games and ran for 122 yards on 31 carries (3.9 YPC) to go along with six receptions for 72 yards receiving.