The move comes hours after general manager Dave Caldwell said to expect changes on defense.
Babich, who became defensive coordinator when coach Gus Bradley took over Jacksonville in 2013, led one of the worst defenses in the NFL each of the past three seasons:
2015: 31st in scoring (28.0); 24th in total yards (375.0)
2014: 26th in scoring (25.8); 26th in total yards (370.8)
2013: 28th in scoring (28.1); 27th in total yards (379. 4)
The move could lead Bradley to take over defensive play-calling duties in his pivotal fourth season.
"We'll look at it as we put it all together and see," Bradley said Monday, via the Florida Times-Union. "That's (one of) the things I think (will be determined) as I gather information and (figure out), 'Where is it at?' I think the obligation is (to) do what's best for this organization. That's why I really want to gather all the information, see what's best and go from there."
With a young, exciting offense, led by record-setting quarterback Blake Bortles, the Jags' defense needs to take a giant step forward in 2016 in order to compete in a weak AFC South.
Owner Shad Khan gave a vote of confidence to Bradley last week, indicating he had faith in the coach to turn around a program that hasn't earned more than five wins a season under Bradley.
Caldwell indicated that he believes pieces are in place for a successful defense and that he plans to focus his offseason -- free agency and the draft -- on stocking that side of the ball.
The Jags are in need of talent on all three levels of the defense. Getting 2015 first-round pick Dante Fowler Jr. back should be a boost to the pass rush.
Spiking the coordinator is just the first phase of the Jags' defensive revolution.