Thomas (ankle) has been ruled out for Sunday's season opener against the 49ers, Chris Tomasson of the St. Paul Pioneer Press reports.
Despite suffering an ankle injury in the Vikings' final preseason game, Thomas made the 53-man roster, but the injury is still serious enough to keep the running back sidelined for Week 1. However, with Dalvin Cook and Latavius Murray leading the way in the backfield for Minnesota, Thomas' absence will have a minimal impact Sunday.