Editor's note: This is the first in a series of occasional offseason stories following the progress of the Green Bay Packers' installation of a 3-4 defense and the challenges facing teams that switch base formations.
With a late-season collapse and a 6-10 record, there was little doubt in Green Bay that there would be some significant changes.
There was talent everywhere, especially on defense, but the personnel wasn't being used at optimum effectiveness. The Packers had one of the top secondaries in the NFL, athleticism at linebacker and an above-average line, yet they weren't creating problems for opposing offenses in the same fashion as the Dallas Cowboys or Baltimore Ravens -- though not many defenses did. Still, the caliber of players weren't that different, so something had to give.
Packers coach Mike McCarthy opted to switch from a 4-3 defensive front to a 3-4, the same scheme run by the Super Bowl champion Pittsburgh Steelers, who had the top-ranked defense during the regular season. McCarthy hired former Carolina Panthers and Houston Texans head coach Dom Capers as his defensive coordinator to take over the scheme and teach it to players and coaches.
The movement of one player off the line and adding one to the linebacking corps might sound simple -- football is just running, throwing, catching and tackling, right? However, such a shift in philosophy could be as radical as switching from the veer option to the spread offense.
"We like the versatility it gives you," Capers said of the 3-4 defense. "Just in very general terms, when you're in a 4-3, it's pretty much predetermined who your four rushers are. In a 3-4, you know three linemen will be your rushers. That fourth rusher can come from one of the linebackers. Then, when you get five rushers, you have a lot of combinations. Hopefully, you've got enough flexibility in packages to rush different combinations in the 3-4 because you have another linebacker-type of player on the field."
In theory, it sounds like a way to counter offenses -- such as the "Wildcat" -- that are becoming more diverse and feature more athletic players at the skill positions. In reality, the production from playing a 3-4, specifically when you have to transition from a 4-3, might not always give you Steelers- or Ravens-type results.
Personnel must be altered. Coaches accustomed to teaching a 4-3 have to learn much of the new defense from scratch. New concepts and disciplines must be followed to the last detail, from the head coach to the third-string nose tackle. Middle linebackers in a 4-3 have to grow accustomed to sharing that space with another linebacker in a 3-4, and that's not always an easy adjustment for some players.
"There will be a transition," Capers said. "How fast you transition into a true 3-4 is based on your personnel and how well they adapt to the things you ask them to do. You've got to be flexible enough to keep some 4-3 elements but also keep enough flexibility to feature your best football players."
Those best football players tend to be the linebackers, especially outside linebackers. Pittsburgh's James Harrison was voted the league's top defensive player and, with his 100-yard interception return of a Kurt Warner pass in Super Bowl XLIII, also delivered one of the most spectacular plays in the big game's lore. Dallas' DeMarcus Ware led the league with 20 sacks, and Miami's Joey Porter was second with 17.5. All three are outside linebackers, tough enough to play as a 4-3 end on run downs yet athletic enough to rush the passer or drop into coverage.
For the Packers, defensive end Aaron Kampman, a tireless player who had 9.5 sacks last season, has been tagged to play the role. He is accustomed to playing with his hand on the ground at defensive end, which he'll still do at times, but he'll also have to fall back into coverage or rush from off the line of scrimmage from a two-point stance.
"The biggest thing is when you play defensive end, you don't have to think," said former Cincinnati Bengals defensive end/outside linebacker David Pollack, whose promising career was cut short because of a serious neck injury. "You line up, you have an assignment and you do that assignment regardless.
"When you move to linebacker, your assignment is predicated on formations. You have to know when it's Cover 2, if they run at me, what to do or what my responsibilities are if you see action away from you. There's a lot more thinking, so it can really slow you down. What killed me is I would have everything right and then a guy would go in motion, and that changed what I was supposed to do.
"When you are (at) end and you're an effective pass rusher, you can get in a rhythm. You can figure out what the guy across from you likes to do when he run blocks or how you can beat a guy when he backs up to pass block. It's different when you play with your hand off the ground."
The micromanagement when playing outside linebacker is why Capers said he'll maintain a lot of the 4-3 principles the Packers have used while making the transition.
The Arizona Cardinals hoped to transition to a 3-4 front after Ken Whisenhunt took over for Dennis Green as head coach in 2007. Former defensive coordinator Clancy Pendergast said they implemented some 3-4 principles, but because of personnel played a "hybrid" front, mixing both elements into the scheme.
The interior linemen didn't always need to eat up two blockers or two-gaps, like most 3-4 defensive linemen have to do. That was the big difference in how they played and why the Cardinals' front typically featured four defensive linemen, although Travis LaBoy, Bertrand Berry and Antonio Smith played as defensive ends and outside linebackers depending on the call.
The biggest change in personnel tends to come on the defensive line. Whereas four-man fronts usually feature a nose tackle in the 300-pound range, another tackle in the 280- to 290-pound range and ends weighing between 255 to 285 pounds, 3-4 lines usually boast a nose tackle who's well over 300 pounds and ends who are between 280 and 300 pounds.
Although Green Bay plans to add at least one outside linebacker, up front, it seemingly has the type of players to fit a 3-4 scheme. Tackles Johnny Jolly and Ryan Pickett are 320 and 330 pounds, respectively. Defensive end Mike Montgomery weighs 273, somewhat undersized when compared to Dallas' Marcus Spears (315) or Pittsburgh's Aaron Smith (298).
The work of a 3-4 lineman is brutal and often unrewarding. Some of the best linebackers in the league -- Baltimore's Ray Lewis and Terrell Suggs; Dallas' Bradie James; Pittsburgh's James Farrior, Harrison and LaMarr Woodley -- play behind human Hummers at nose tackle in Haloti Ngata (Ravens), Jay Ratliff (Cowboys) and Casey Hampton (Steelers), as well as mammoth ends.
"You've got to have the personnel to make it work," New Orleans Saints defensive line coach Bill Johnson said.
Johnson was with Dan Reeves' Atlanta Falcons staff when Wade Phillips was the defensive coordinator and took over as interim head coach. Under Phillips, the Falcons switched from a 4-3 to a 3-4. The personnel wasn't ideal, and after a few seasons -- and a coaching change to Jim Mora in 2004 -- the Falcons reverted back to a 4-3, the scheme they still play.
"The problem they had in the 3-4 scheme wasn't with one game," Johnson said. "There were 16. It takes large men to play that 3-4 over the course of the season. You've got to hold some people off those linebackers, so it takes good-sized people and some luck.
"To have that defense be highly effective, it takes special people playing off the edge at outside linebacker. If you lose one of those guys, they're hard to replace. You've got to have not just good starting personnel but depth.
"I prefer a 4-3, but there are some beautiful things about a 3-4."
Mainly, Johnson said, it is very difficult for quarterbacks to diagnose pre-snap reads when facing a 3-4. In a 4-3, the middle linebacker and safety tend to dictate where the rush is coming from and what pass coverage has been called.
In a 3-4, one outside linebacker could show blitz and the other could come -- with the safety, cornerback or inside linebacker. Or, as Harrison showed in the Super Bowl, he could be on the line of scrimmage, feign a pass rush and step back into coverage.
Even though the 3-4 has been around for years, Capers believes it could be a neutralizer against offenses that are using more plays more often -- plays that used to be called only on third downs, when defenses went to nickel or "sub" packages. He views it as a defensive scheme that gets the best athletes on the field and forces more mismatches than a 4-3.
"If you've got a number of linebackers with outstanding athletic ability, you can match up better with all the athletes offenses are putting on the field," Capers said. "It's possible to match all that ability on defense. You've got to be able to match up your skill with their skill."
The Packers' change in defense will take time. Right now, coaches are spending in-season hours in meetings being taught the scheme and its nuances by Capers. Later, they will be challenged to teach it to players who might not have ever spent time in the scheme. Much of what Green Bay does with the draft and free agency will be dictated by the switch.