Coach Dan Mullen confirmed Robinson's injury on Monday after practice, saying the 6-foot-8, 325-pound senior tore an anterior cruciate ligament during a scrimmage on Friday night.
Robinson has appeared in 37 career games, mostly on special teams, but was the likely starter at right tackle this fall. Some of the candidates to fill the vacancy include Rufus Warren, Justin Senior or Cole Carter. Mullen could also move Justin Malone from guard to tackle.
Mississippi State opens its season on Aug. 30 at home against Southern Mississippi.