SOUTH BEND, Ind. -- The two-deep for No. 24 Notre Dame is no longer two deep on defense.

Even for Notre Dame coach Brian Kelly, who like a lot of coaches operates on the principle of next man up, that's a concern.

''We are running out of next men,'' Kelly said Sunday. ''We're at that point where from a defensive standpoint, and particularly the defensive line, we're left with very few options.''

Kelly got a bit of good news Sunday, though, announcing through spokesman Michael Bertsch that nose guard Louis Nix III, who missed the past two games with knee tendinitis and a small meniscus tear, would practice this week. Bertsch made the announcement Sunday evening after Nix underwent an MRI, although Bertsch said he had no further information. Nix's replacement, Kona Schwenke, is out with a high ankle sprain sustained late in the 38-34 win against Navy.

Backup linebacker Ben Councell sustained a season-ending knee injury against, although Kelly declined to be specific about the injury. Starting defensive end Sheldon Day aggravated a high ankle sprain against Navy and may be ready to play when Notre Dame (7-2) faces Pittsburgh (4-4) on Saturday, although Kelly said that previously when Day missed four of five games.

Starting safety Austin Collinsworth sustained a strained neck against Navy and is scheduled to undergo an MRI on Monday. The other starting safety, Elijah Shumate, who missed the previous three games with a hamstring injury, is expected to be ready for Pitt, Kelly said.

Kelly compared Notre Dame's injury situation against Navy to a scene in the movie ''Apollo 13,'' when an oxygen tank exploded as astronauts were en route to the moon and NASA scientists threw items on a table and said those were all the materials they had to fix the deadly carbon-dioxide gas level in the spaceship.

''That's what we did this week. We threw it all on the table, and we figured out how to get it done. That's why I'm proud of the guys,'' Kelly said. ''We didn't complain about it. It's part of the game. Injuries happen. You've just got to find a way to get it done, and they did. We found a way to get it done.''

Romeo Okwara, a 258-pound outside linebacker, was forced to play defensive end against Navy and may be the backup at both positions against Pitt. Okwara had been listed as the third-string outside linebacker two weeks ago, but moved up a notch after Ishaq Williams sustained an anterior cruciate ligament injury against Air Force.

Kelly said there will be a number of players working on learning different positions this week.

''It becomes an issue now where we have to be very creative in what we're doing and how we're doing it. That's why I don't want to commit to anything today on Sunday because we have some more work to do in terms of looking at our personnel,'' he said.

At least part of the reason for the rash of injuries is facing Air Force and Navy, which both run option offenses and use cut blocks, in back-to-back weeks, Kelly said. In 23 years as a head coach, Kelly said he can't remember ever seeing so many injuries on defense, although he said he has seen it on the offensive side. The Irish offense has some challenges as well.

The Irish lost starting right guard Christian Lombard to a season-ending back injury two weeks ago and left guard Chris Watt sat out against Navy with a posterior cruciate ligament tear, although Kelly expects him to be able to play against Pitt. Kelly said Watt just needs more time to adjust to playing with the injury.

''I think as he adapts to it this week, I think he's going to feel a lot more comfortable,'' he said.

As for the rest of the injuries, Kelly hopes it doesn't get any worse. At least the Irish have a week off after the game against Pitt. Anyway, Kelly said it does no good to complain.

''They don't give you any points for complaining about it. If they did, I'd complain every minute,'' he said. ''So we just take care of it internally and get the next guy ready.''