The 2009 Fighting Irish defense was deemed a failure by fans and experts alike, ranking 86th in total defense, 102nd in yards per play and 101st in yards per carry. Jon Tenuta, thought by many to be one of the finest defensive coaches in the game, was described as the anchor that sunk the Weis era.
When coach Brian Kelly announced that he would be bringing Bob Diaco with him to Notre Dame to serve as defensive coordinator and inside linebackers coach, the same positions that he held at the University of Cincinnati, it looked to be a step in the right direction. In 2009 with the Bearcats, Diaco was charged with the task of replacing 10 starters yet finished the season with a top 10 ranking in both sacks and tackles for loss. Diaco's first task was to reinstall the 3-4 defense that Corwin Brown installed under Charlie Weis.
Bob Diaco was an All-Big Ten linebacker and a semifinalist for the Butkus Award during his playing days at Iowa, under Hayden Fry. During his coaching career, he learned under Al Groh who was instrumental in revolutionizing the 3-4 defense along with Bill Belichick and Bill Parcells.
There is absolutely no downside when you learn a defense from those coaches. Coming from the linebacker position, which is basically the defensive play-caller, and broadening his defensive coaching skill under a group of defensive masterminds, is an extremely promising situation.
Defensively, this season has had its ups and downs, but that has to be expected with a new coaching staff, implementing new and different schemes. The Notre Dame defense held Boston College to five yards rushing, Western Michigan to 37 and Utah to 71. The Irish defense also held Army to 39 passing yards.
At first glance the numbers for the Michigan game would look brutal with Michigan rushing for 288 yards, but only 30 of those yards were by anyone not named Denard Robinson. One of the major lowlights has to have been giving up 438 total yards to Navy, 367 coming on the ground.
After 11 games, Irish opponents are averaging 3.9 yards per rush, 11.8 yards per catch and 385.7 yards per game total offense. According to USA Today the Irish are the No. 55-ranked defense in the country right now, a little better than midway in the 120-team rankings, but they are up from No. 91 after not giving up a defensive touchdown in the last 13 quarters.
Looking at the defensive depth chart going into tomorrow night's game against USC, there are four seniors starting on defense—three in the defensive backfield—so the first and second levels of defense will be pretty much intact next year. Experience-wise this will provide great dividends to players like outside linebacker Dan Fox and nose guard Louis Nix III who can step into the mix next season, as well as defensive verbal commits Stephon Tuitt and Tony Springmann.
What it all amounts to is when things started to look bad after losses to Navy and Tulsa, instead of just mailing it in and finishing off the season as quickly as possible, the Irish defense seemed to rally around Bob Diaco and embrace his strategy. Diaco himself showed his adaptability when he switched to a four-man front for the Army game.
One has to wonder what would have happened if he had made that adjustment at halftime of the Navy game, bringing up an extra down lineman and dropping the linebackers back a yard, to give them a better view of what was developing in front of them. Hopefully, if faced with that situation in the future Diaco will make the proper adjustments.
The way that it appears right now is that the defense as a unit has bought into the philosophy that Diaco is preaching. With everyone onboard the future for the Irish defense can be extremely bright.