Notre Dame could be without two starters on defense when the Irish (6-2) play host to Navy (4-3) on Saturday.
Coach Brian Kelly said linebacker Ishaq Williams, who injured his knee in Saturday's 45-10 win at Air Force, and nose guard Louis Nix III, who didn't play against Air Force because of knee tendinitis, are questionable to play this weekend.
"It will depend on his practices and the quality of his practices," Kelly said during his Sunday teleconference of Nix's availability against the Midshipmen. "It's really hard to say until we really get out there. I think he is right now questionable until we get a chance to see him practice."
Williams started against Air Force, but the junior had to leave the game early after injuring his knee.
Kelly said he is confident that backups Romeo Okwara, Ben Councell and Justin Utupo can step in again for Williams against another option-based team in Navy.
"We got a lot of guys involved (against Air Force)," Kelly said. "I don't want to provide too much cliché, but for us, next man in really went in there and showed well for us. I think if we just continue to roll those guys out there, we are in pretty good shape."
The Irish appear to be in good shape with two other starters who suffered injuries against the Falcons.
Left guard Chris Watt, who strained his knee, and defensive end Sheldon Day, who re-tweaked his ankle, are probably to play against Navy, Kelly said.