Jackson suffered a torn meniscus during Sunday's game versus the Dolphins, Dane Mizutani of the St. Paul Pioneer Press reports.
Per Ian Rapoport of NFL Network, coach Kevin O'Connell said Monday that Jackson will miss at least the remainder of the regular season. There still seems to be a possibility he could return for the postseason in the event that the Vikings get there, but for now, Joe Huber projects to step in at left guard.