"Some say the 46 defense is just an eight-man front. That's like saying Marilyn Monroe's just a girl."- Buddy Ryan, Chicago Bears former defensive coordinator and creator of the 46.
The 1985 Bears were arguably the greatest team of all time. But what made the 15-1 Bears so dominant? The pass game was average. The run game was sweetness. The defense, most importantly, was monstrous.
The Bears' defense coordinator, Buddy Ryan, designed the 46 defense when he arrived in Chicago in 1978. Ryan inherited a team that was atrocious at stopping the run and rushing the passer. He designed the 46 to essentially be an ultra-aggressive version of the 4-3 defense.
The defense started off as a simple blitz package, but by 1981, it was Chicago's base defense. By 1985, Ryan had finished tweaking and perfecting his brainchild, and by then it was nearly unstoppable.
The personnel is the same as in a 4-3 defense, possessing four down lineman, three linebackers, two corners and two safeties. The difference was in the lineup.
One the weak side, the defensive end lines up outside of the tackle. The defensive tackle lines up on the weak-side guard. On the strong side, the defensive end is head up on the strong-side guard and the tackle is lined up over the center.
The "jack" linebacker, or the strong-side backer, lines up outside shoulder to the tight end on the line of scrimmage. The "charlie" linebacker, or the weak-side backer, lines up on the tight-end's inside shoulder. These two could either pin their ears back and rush the passer or they could drop back in coverage. The "mike" backer lines up directly across from the strong-side tackle and two yards back.
Doug Plank, the strong safety for whom the defense was named (his jersey number was 46), played as a hybrid safety-linebacker. He lined up directly in front of the weak-side tackle and a couple yards back. The free safety lines up 12 yards back and over the weak-side guard. The corners line up on their receivers.
The 46 essentially put a steel wall of defenders in front of opposing offenses, forcing them to throw the football. The eight-man front made it extremely difficult to run against the 46, but it was vulnerable to short passing routes. The corners would play bump and run coverage, in order to disrupt the quick, "West Coast-type" patterns that were so dangerous to this defense.
Buddy Ryan used the formation to create mismatches, overload gaps, and make life miserable for offensive linemen. The defense put a defender directly in front of every lineman, making it difficult to execute second level blocking. Pulls and traps were also limited by the formation, as each lineman had to account for the defender immediately in front of him.
The Bears' run defense was top two in both run and overall defense every year from 1984-1988. So why is the 46 so uncommon now?
First off, the 80's Bears had one of the best front sevens of all time, including Hall of Famers Mike Singletary and Dan Hampton and All-Pro selections Wilber Marshall and Richard Dent. Also, their corners were extraordinary at pressing receivers, making them the perfect fit for the 46.
No modern team has the talent to run this defense effectively.
Buddy's son, Rex Ryan, and the New York Jets ran it occasionally in 2009, but its not their base defense and they have a very gifted secondary. Today's emphasis on passing makes it to too risky to field an eight-man front as a base defense.
Buddy Ryan was ever the innovator. He was a mastermind at disguising coverages and creating havoc in the backfield. He was adept at designing defenses that fit his team's strengths and hid their weaknesses.
The 46 was specially tuned to the personnel of the '80s Bears, which is why few teams use the 46 nowadays, and why no one uses it as a base defense.