The Changing Face of Defense in the NFL By TarkentonToJones on Jan 26, 2021, 10:59am EST +
From Tom Bliss, a data scientist at the NFL league office: The traditional 4-3 and 3-4 defenses (with 4 DBs) we all grew up watching are gradually heading toward extinction. In 2007, those defenses accounted for a bit more than 50% of the plays run across the league, and adding in a regular nickel defense with a slot CB (4-2-5), were seen on almost 75% of the plays.
But over time, with passing becoming a more and more important part of NFL offenses, things have dramatically changed. In 2020, traditional 4-3 and 3-4 personnel groupings were only used about 25% of the time. Regular nickel defenses are now much more common, and more exotic defenses like 3-3-5, 2-4-5, and 2-3-6 now account for about 20% of all defenses played.