Sheridan, whose 50th birthday is Jan. 27, has been the team's linebackers coach for the past four seasons.
"Bill is a very good football coach," Coughlin said. "He does an excellent job of teaching, of reinforcing what we aspire to be with our defensive team. He's coached our linebackers, he's given a big assist to Steve in all that he has done. As a linebackers coach, you're a central figure in the spoke, because you're involved in the coordination of the front and the linebackers and then the back seven. He has done a good job of encompassing the entire defense and grasping the aggressive style."
"Obviously, I'm thrilled," Sheridan said. "I'm humbled but very, very excited and anxious to get going. I've prepared my entire career for this opportunity. I owe this to Tom Coughlin and Steve Spagnuolo and the rest of the defensive staff – Peter Giunta, Mike Waufle, Dave Merritt and Andre Curtis. This is nothing more than a reflection of the success we've had here."
Sheridan said he will keep Spagnuolo's system in place but will modify it according to his preferences and the players' strengths.
"I'm sure, as much as anything, that's Tom's motivation for promoting from within, whether it was me or Peter Giunta – to keep the defense in place," Sheridan said. "It's obviously a proven, excellent system that Steve brought from Philadelphia. You're obviously going to have a slightly different tint to it, because you have a different coordinator and will get different input from whoever Tom brings in from outside to complete the staff. But the system is in place and there's a tremendous comfort level with the players."
Coughlin interviewed both Sheridan and Giunta, the secondary coach/cornerbacks, who was the defensive coordinator for the Rams team that won Super Bowl XXXIV following the 1999 season. Coughlin said he was impressed with both coaches. He informed both coaches of his decision early in the morning on Jan. 19.
"Both were very good," Coughlin said. "Peter has been a coordinator before. I just felt in my gut that Bill would be the right choice."
All-Pro defensive end Justin Tuck endorsed Sheridan as the new defensive coordinator.
"Coach Sheridan is a very knowledgeable football guy," Tuck said. "He's a quality coach. It's good that we kept it in-house so we can continue to improve on a successful defense. I'm very excited to see what coach Sheridan will do in his new role."
Sheridan said he learned much from Spagnuolo in their two years together.
"Not just the scheme itself – the fundamentals of the scheme itself and the pressure package," Sheridan said. "I think Steve did a great job of looking at our defense as our opponents did, with a self-scout mentality. He was always trying to be one step ahead with regard to how we were being viewed by our opponents."
Sheridan came to the Giants from the University of Michigan, where he coached the linebackers in 2002 and the defensive line the following two seasons. He coached the safeties and special teams at Notre Dame in 2001 and the linebackers at Michigan State from 1998-2000. Sheridan also had coaching stints at Maine, Cincinnati and Army.
"I liked the fact that he had great versatility," Coughlin said of his initial decision to bring Sheridan into the NFL. "He had coached the linebacker position, the defensive line position and the secondary. And he coached at some great places – Michigan, Notre Dame and Michigan State. He'd been at Army with Bob Sutton. He had been at some outstanding programs and schools that not only win but are very high in tradition. He had been exposed to different coaches and people that I have respect for and he came very highly recommended."
Sheridan Named New DC
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