Jim Wyatt's report that the Titans are considering Eric Mangini for their vacant defensive coordinator position naturally made me wonder. If Mangini is hired, would the Titans change to a 3-4 defense, where Mangini's experience lies?
My first inclination is to believe it won't happen. Jeff Fisher will be coaching to keep his job this year. Now is not the time to make changes which usually take several years to implement.
The length of time before a successful transition to the 3-4 is complete depends in large part on the pieces you already have in place. When the Packers made the switch in 2009, they already had the big bodies up front that a 3-4 requires, in Ryan Pickett, Johnny Jolly and Cullen Jenkins. They also had Aaron Kampmann, who was able, sort of, to make the change from 4-3 defensive end to 3-4 outside linebacker. The Pack had the good fortune to draft Clay Matthews as their other OLB, and they suddenly had the makings of a good front seven.
Other teams aren't as fortunate. We recently saw the Jaguars try the 3-4 as a part-time defense, then try to make it their full-time defense, unsuccessfully. They're back to a base 4-3 again after that failed experiment.
Do the Titans have some of the pieces in place for a 3-4 defense? Let's take a look.
A few key points to note here. The 3-4 requires much larger players than the 4-3, as shown below. The nose tackle is the key and good ones are at a premium. You can't have a good 3-4 defense without a good nose. Outside linebackers are the other key. They have to be big enough to take on offensive tackles and fast enough to cover running backs. You can make do, somewhat, with average defensive ends and inside linebackers.
Ideal sizes for 3-4 personnel:
Nose tackle: 320 pounds and up, average weight 325*
Defensive ends: 300 pounds and up, average 306
Outside linebackers: 250-265 pounds, average 256
Inside linebackers: 240-250 pounds, average 244
* Average weights based on personnel from the best 3-4 defenses: the Steelers, Packers, Ravens, Jets, Patriots and Chargers.
The Steelers have some anomalies in undersized players, such as OLB James Harrison, 242 pounds; ILB Lawrence Timmons, 234; and DE Brett Kiesel, 285. Pittsburgh is by far the smallest among the best 3-4 defenses. Without them, the average sizes in the above paragraph would be larger.
These are the sizes of some of the other best 3-4 players, and the sizes of the players the Titans should try to get if they go to a 3-4:
NT: Casey Hampton, 325; B.J. Raji, 337; Vince Wilfork, 325
DE: Haloti Ngata, 337; Ty Warren, 330
OLB: Clay Matthews, 255; Lamar Woodley, 265; Terrell Suggs, 260
ILB: Ray Lewis, 250; A.J. Hawk, 247
Following is how the Titans' personnel would stack up if they tried to convert to a 3-4:
Nose tackle: Nobody on the roster is suited to play NT. Two NTs would have to be acquired in free agency and/or the draft, both the starter and a backup. This will be the number one priority if the Titans switch to a 3-4.
Defensive ends: Basically, the Titans would need to switch all their defensive tackles to DE. Tony Brown and Sen'Derrick Marks could be decent, though not great, fits. They'd work for a while, but would eventually need to be replaced with larger players. If the Titans make the switch to the 3-4, Jason Jones would be the smallest 3-4 DE in the league. The Titans would definitely need to acquire a 300 pound plus guy to complement the others.
Outside linebackers: Jason Babin, Jacob Ford and Dave Ball have the body type but there are big question marks about them. Babin started his career as a 3-4 OLB with the Texans. Houston later benched, then released, their first-round draft pick when it became apparent he wasn't a good fit at that position. All three would have problems in pass coverage, in my opinion. Even though Derrick Morgan is larger than the typical 3-4 OLB, he might be a fit. He would also have questions about being able to defend the pass. If they make the switch, the Titans would need to pick up one OLB in the offseason and try to make do with what they have to fill the other OLB spot.
Inside linebackers: As noted above, average ILBs can suffice in a 3-4. There are also some great ones around the league, such as Timmons and Lewis. For the Titans, Will Witherspoon, Stephen Tulloch and Gerald McRath could all fit here. ILB wouldn't be a top priority for the Titans this offseason, especially if you had Spoon in the middle to keep on the field in nickel packages. This is a position that would need an upgrade, especially in pass defense, but one where you could try to get by for a year with what you have.
As you can see, there would be a lot of square pegs trying to fit in round holes here. We're looking at adding four or more players in the offseason to make it work and two of them, the NT and an OLB, will need to be high quality, star players. Do you commit your top two draft picks to these positions when there are so many other needs? Like it or not, that's what it will take if you want a good, and not a mediocre 3-4.
Also, it should be noted that the Titans' best defensive player last year, Jason Jones, would be playing out of position, as would the Titans' first-round draft pick, Morgan. More square pegs and round holes. A switch to a 3-4 just doesn't make a lot of sense in the short-term.
Although I like the 3-4 and I hope the Titans will switch to it sometime in the near future, I doubt if it happens in a year when Jeff Fisher needs to win a lot of games to keep his job.
Point after: The top three defenses this season (fewest points allowed) were all 3-4 defenses - the Steelers, Packers and Ravens.