"We're still getting a little bit more information," Kelly said during his weekly teleconference. "We had an MRI. I'll probably have a little bit more specific details, but he's out for the season."
Martin left the first quarter of Notre Dame's 23-13 win Saturday over BYU, though the redshirt sophomore was able to walk off unassisted. Kelly said after the game Martin had hyper-extended his knee.
Redshirt sophomore Matt Hegarty replaced Martin at center for the rest of the game and will start in the Irish's final two games: Saturday at Stanford and their to-be-determined bowl game.
Martin, a first-year starter, started all 11 games this season and was playing Saturday's game with a "boxer's fracture" in his right hand suffered two weeks earlier in a loss at Pittsburgh.
He is the second starting offensive lineman Notre Dame has lost to significant time this season, as right guard Christian Lombard underwent back surgery and was shut down for the year after an Oct. 19 win over USC. Steve Elmer and Conor Hanratty have since filled in at right guard.
Martin's older brother, left tackle Zack Martin, made his 50th consecutive start Saturday, matching the school record established by Sam Young from 2006-09.