Irish 'D' has done wonders for Kelly in 2012

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Brian Kelly has had plenty of reasons to be happy this season.In which area has Notre Dame coach Brian Kelly had the biggest impact?

The answer is fairly clear: the defensive side of the ball.

Kelly’s Irish have allowed an average of 17 points per game since he took over as head coach, which will be the best by a Notre Dame coach in his first three seasons since either Lou Holtz (whose teams allowed 16.9 points per game in his first three seasons) or Dan Devine (12.3), depending on how the team fares in the BCS Championship.

Even factoring this year’s team out, the defensive numbers for the Irish in his first two seasons were more favorable than those under Bob Davie, Tyrone Willingham, and Charlie Weis.

This year’s team is Notre Dame’s best in a long time.

Notre Dame has allowed 124 points this season and will almost certainly end the season having allowed its fewest since 1996 (when it allowed 181). It has a chance to be the first Notre Dame team to hold its opponents to fewer than 150 points since the 1980 team yielded 128.

Notre Dame Defense
2012 Season

In fact, if Notre Dame holds the Crimson Tide to fewer than six points, it will be the first Irish team to allow fewer than 10 points per game since the 1973 team allowed 89 points in 11 games.

The previous nine Notre Dame teams allowed an average of 298 points per season (24 per game), with the seven before Kelly’s arrival yielding 307 per season.

This year's Notre Dame's defense has excelled in just about every opportunity.

Opponents ran 95 plays inside the red zone this season against the Irish and were sacked more often (nine times) than they got into the end zone (eight times).

In the previous eight seasons, Notre Dame opponents scored at a rate of about once for every five red-zone plays they ran. They were sacked an average of less than twice per season.

Notre Dame had allowed at least two yards per rush on plays inside the red zone in each of the last seven seasons. This season, they’ve allowed 54 yards on 60 such runs.

Regarding their defensive prowess in other areas, consider this stat:

The Irish haven’t allowed a touchdown outside the red zone over their last 628 plays. The next-longest streak this season is Vanderbilt’s 387.