"I'm very excited to add Jeremy to our staff," Fisher said in a statement. "He brings a lot to the table. He's one of the bright young coaches in college football. He's done an outstanding job at Alabama and in the past as a great high school coach. He's also a good recruiter, but most importantly of all, he's a great person."
Pruitt will replace Mark Stoops, who was recently named head coach at Kentucky.
Pruitt's move to Florida State was initially reported over the weekend by several media outlets such as 24/7sports.com and AL.com.
"This is a great opportunity for me to join another one of the top college football programs in the country and take over as defensive coordinator for one of the best defenses out there," Pruitt said. "I've enjoyed my time at Alabama and am grateful to Coach Saban and my Crimson Tide family for their support in preparing me as I begin the next chapter in my coaching career."
Pruitt, 38, has spent the last three seasons in Tuscaloosa and was known as one of Nick Saban's top recruiters. He was also the only coach on staff who had played for the Crimson Tide (1995-96 under Gene Stallings). He is expected to coach Alabama in the national championship on Jan. 7.
"Jeremy did an outstanding job for us and the opportunity for him to become the defensive coordinator at Florida state is well deserved," Saban said. "We always want our coaches to grow and advance in the profession and Jeremy has worked very hard through the years to earn this opportunity and put himself in this situation.
"We appreciate all that he has done to contribute to the success we've had at Alabama and wish him the best in his new role."
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