Alabama used its stout defense—which gave up just 276.3 yards per game and 4.3 yards per play—to roll all the way to the national title a year ago.
That defense was paced by its fast and physical front seven led by defensive end Jonathan Allen, pass-rush specialist Tim Williams and a front seven that was deeper and more versatile than any in the country.
"You need a lot of depth, you need a lot of athletic guys that can make plays in space, can rush the passer," head coach Nick Saban said at SEC media days.