Is new defensive coordinator Bob Diaco the answer to Notre Dame's desperate defensive problems? Or will the move prove a step too steep for the former University of Cincinnati top defense guy?

On the surface Diaco is by far the biggest gamble of the Brian Kelly era so far. His Bearcats defense was rated only 67th nationally and allowed almost 40 points per game in its last five games.

Notre Dame's leaky defense allowed almost 400 points per game and ranked 86th, somewhere up there with Montana State and Appalachia U. There is no bigger job on the Notre Dame staff.

Diaco certainly thinks he has the goods to deliver. "I'm an aggressive person and an aggressive coach," Diaco said in a statement. "There will be consistency, there will be detail, there will be aggressive coaching. I'm an energized, positive person who loves what I do."

He is helped by the decision of standout freshman linebacker Manti Te'o to come back for his second year. It was feared that he would leave and fulfill his obligation as a Mormon missionary. However, over the Christmas season Te'o made it clear he will return.

"My decision is to come back to Notre Dame and prepare for the next football season," Te'o said in a press release "I mainly talked to my parents and sometimes some of my family members to get their input. They were all quite supportive. I also talked to my bishop up in South Bend. "

Diaco still has lots to worry about. Charlie Weis's defensive guy Jon Tenuta had a similar reputation of getting it done when he arrived in Notre Dame. Diaco and he have similar philosophies – pressure, pressure, pressure – which means lots of blitzing. That proved to be a disaster in 2009.

Brian Kelly is the one guy who does not seem to have many doubts. He called Diaco "one of the rising stars in this profession." Diaco fans point out that he lost 10 starters this year and still produced a defense that, apart from late season problems, performed very well.

Make no mistake, however, Diaco will be under almost as much pressure as Kelly to produce. Welcome to the Notre Dame hothouse Bob.

Is Bob Diaco a gamble for Notre Dame?