Notre Dame starting free safety Jamoris Slaughter suffered a torn Achilles tendon in Saturday's 20-3 victory over Michigan State, and it will keep him out of action the rest of the season, Irish coach Brian Kelly told reporters on Sunday.
Kelly said Slaughter will have surgery sometime this week.
Slaughter is a fifth-year senior, but he could petition the NCAA in an attempt to get a sixth year of eligibility.
He has eight tackles this season and had 45 tackles, two sacks and an interception last season.
Sophomore Matthias Farley will take Slaughter's spot in the starting lineup when No. 11 Notre Dame (3-0) hosts 18th-ranked Michigan (2-1).
Slaughter has missed time in several games this season.
"The last couple weeks we've played a lot of football without him, especially in the second half, times where teams are throwing the football," Kelly said. " We've done a nice job there."