What to watch from Notre Dame in Saturday's game against Purdue:
1. Air defense: The Irish were nearly defenseless against the pass, ranking 76th nationally in that category and getting burned deep routinely. Now they'll take on a Purdue team that averaged 255 passing yards a game last year and adds Miami transfer Robert Marve at quarterback. Notre Dame cornerbacks Darrin Walls and Gary Gray won't be left out on an island as much as they were last year, but they will still face a heavy test against the likes of receiver Keith Smith.
2. Dayne's debut: Coach Brian Kelly won't be the only high-profile debut for the Irish. Quarterback Dayne Crist makes his first-ever start and will try to follow the impressive season Jimmy Clausen produced last season. Crist is the key to this offense and should have opportunities to make big plays against an unseasoned Purdue secondary. He'll also have to withstand his first hit since tearing his ACL last season.
3. Linebacker lounge: The linebacking unit might be the most intriguing position on the field for Notre Dame in the return to the 3-4. Manti Te'o should begin to assert his superstar status in the middle and Darius Fleming is expected to be a playmaker at one of the outside positions. But there was heavy competition at the other spots, and Kelly promised to rotate a lot of players. Since the linebackers will be needed to help in pass coverage and to pressure Marve, they'll all have to play well.