The offensive coaching staff remains entirely unchanged, which is pretty boring for offseason article purposes but pretty great for Spartan fan purposes, since they oversaw the best offense in school history last year. So let's take a look at the Spartans' new-look defensive staff.
He Gone: Pat Narduzzi
Narduzzi joined Dantonio's staff as defensive coordinator at Cincinnati in 2004. When Dantonio came to Michigan State before the 2007 season, Narduzzi followed and stayed in the DC post up until this offseason. Narduzzi is now the head coach at Pitt, becoming Dantonio's third former assistant to take a head coaching job. Interestingly, no MSU assistants left with Narduzzi for promotions at Pitt; whether that's a function of loyalty to Dantonio, the assistants' disinterest in Pitt, or Narduzzi wanting to create a program in his own image is unclear, since we don't even know if Narduzzi asked any other MSU assistants to go with him.
At MSU, Narduzzi's defenses consistently ranked in the top 10 in rushing and total defense, filled the All-Conference teams over the last several years, and most recently put MSU on the short list of programs which have had cornerbacks drafted in the first round in consecutive years. For his efforts, Narduzzi won the Broyles Award as the nation's top assistant coach in 2013. Not bad for a guy who was a target of 'Fire Narduzzi' demands from the fanbase as recently as 2009 (though, to be fair, that defense was a tire fire; turns out it's hard to play a press man scheme when literally none of your inherited corners can do that).
He Promoted: Mike Tressel, Co-Defensive Coordinator
Tressel has also been with Dantonio for a while now, having joined up when Dantonio was named HC at Cincinnati. Tressel formerly served as the linebackers and special teams coach. MSU produced three All-American linebackers on his watch (Greg Jones, Max Bullough and Denicos Allen), and had generally successful special teams play as well, particularly in the invaluable punt game with Aaron Bates and Mike Sadler. As I'm obligated to mention every time I bring him up, yes, he is related to Jim Tressel. Mike got his start in coaching as a graduate assistant on uncle Jim's 2002 national title team. Although a new coach was hired at Tressel's old position, he will continue coaching the linebackers as well.
He Also Promoted: Harlon Barnett, Co-Defensive Coordinator/Assistant Head Coach
Barnett has deeper roots with MSU than anyone else on the coaching staff, having been an All-American defensive back for George Perles in the 1980s before a 7-year pro career. As the defensive backs coach, Barnett has likely benefitted from Dantonio's personal expertise in this area; 8 of his former charges have gone on to NFL careers in some form, and Darqueze Dennard won the Thorpe Award as the nation's best defensive back under Barnett's coaching.
Although Barnett and Tressel have been named co-coordinators and will apparently both be in the booth during games, it's worth noting that MSU hired a new coach for Tressel's old position, but not for Barnett's. It seems reasonable to infer this means Barnett will continue working heavily with the defensive backs. Don't assume that means less responsibility for Barnett, though; he also picks up the title of assistant head coach which Narduzzi used to carry.
He New: Mark Snyder, Linebackers/Special Teams Coach
Snyder is yet another former member of the Jim Tressel '02 Band to reunite in East Lansing (with Dantonio, Mike Tressel, and co-OC Jim Bollman). Snyder's most recent coaching stop was less than a rousing success, as he was fired as the Texas A&M defensive coordinator after three seasons. He also had a stint as Marshall's head coach from 2005-09 without much to show in the way of results.
The introductory press conferences depicted Snyder as a fiery personality and an effective recruiter, both accurate descriptions of Narduzzi as well. Although his recent history hasn't been glorious, plugging in a guy with coordinator and head coaching experience as a position coach will probably yield decent results. This hire is comparable in a lot of ways to bringing Jim Bollman aboard; Snyder had been cast out from his last position, and his longstanding relationship with Dantonio caused a bit of rumbling about Coach D hiring over-the-hill friends in need of work (nevermind the fact that Bollman had a job at Purdue when Dantonio brought him on). The rumbling was less audible this time given how well Bollman has worked out, and Snyder will have returning starters at most of the positions under his guidance to work with.
Overall Outlook: Maybe This Will Be Fine?
Losing a coordinator of Narduzzi's caliber isn't going to be a seamless transition, especially with two guys taking the job instead of one. When longtime OC Don Treadwell left the team after the 2010 season, the offense coasted on the unit he built for the 2011 season, but then took about another year and a half to find its footing again, and ultimately didn't do so under the guy who replaced Treadwell.
Venturing a guess, this changeover will probably be easier because of Dantonio's personal experience on the defensive side of the ball. One assumes that after Treadwell left, Dantonio may have felt reluctant to interfere with his new OC, even when things went disastrously in 2012. On his preferred side of the ball, Dantonio will probably be more comfortable stepping in if there are issues. 2014 proved that this defense isn't invincible, so new voices having input may be a good thing anyway (do not interpret that as "Good Riddance Narduzzi"). Moreover, it's not even clear at this point how much of the scheme was Narduzzi's versus Dantonio's anyway. But we're about to find out.