Defenses are gauged and weighed by the ability on three different levels.
From the defensive line to the linebacking corps to the secondary, at least a marginal level of playmaking ability must exist for the 11-man group to find success. An imperfect stress point can cause a stop unit to have flaws.
In 2015, Tennessee ranked No. 2 in the nation in opponent third-down conversion percentage. The Volunteers found a way to get off the field more times than not.
When foes rolled the dice, unfortunately for the Volunteers, opposiong offenses moved the chains 18 of 24 times (.750). That ranked 124 out of 127.
John Jancek is out as coordinator over a group that includes All-SEC caliber players such as Derek Barnett, Jalen Reeves-Maybin and Cameron Sutton. In is Bob Shoop, who passed on opportunities at programs like Auburn and LSU to leave Penn State for Knoxville.
Will the change signal Tennessee winning more games than the previous season for the third year in a row under Butch Jones?
Find out more about the Vols defense by listening to former Tennessee receiver Joey Kent and IT's Danny Parker in the Insider Report video above.