Last season, Wade Philips created one of the best defenses in the NFL when he led the Houston Texans' transition from a 4-3 defense into a 3-4 scheme.
Through the draft and free-agency additions to his secondary, Philips was able to quickly complete the turnaround from one of the worst defenses in the league in 2010.
The Texans aren't the only team to abandon the customary 4-3 defense and move to the 3-4 scheme in recent years. Prior to winning the Super Bowl in 2011, the Green Bay Packers brought in Dom Capers to run their 3-4, which saw Aaron Kampman move on and Clay Matthews move in.
In fact, in today's NFL, 12 teams now run the 3-4 scheme as the base, or substantially at least, defense. Two teams are moving back to a 4-3 defense after playing the last few seasons in 3-4 schemes, but the competition for 3-4 pieces, which aren't that common, has never been higher.
Considering that three of the first 11 picks in last year's NFL draft were taken to play, initially at least, in 3-4 fronts and seven first-round picks in total, were pieces brought in to play specific roles in 3-4 defenses, there has been a certain change in focus in the NFL in recent years.
Not so long ago, the Pittsburgh Steelers were able to find fits to their defense in the latter rounds of the draft and with free agents who didn't fit in their previous schemes.
Instead of spending a top pick on a guy like JJ Watt or Marcell Dareus to build from the front, they were able to bring in future stars like Aaron Smith in the fourth round or Brett Keisel in the seventh. Keisel and Smith have given the Steelers years of quality play at a cheap price.
It wasn't just on the defensive line, however, picking up a bust from New York in free agency turned into James Farrior, while James Harrison couldn't find a home for a long time in the NFL, with the Steelers and Ravens cutting him. Other teams never went for Harrison because he was too small to play end in a 4-3.
These days, the competition for players like Harrison, Smith, Keisel and Dareus or Watt is fierce. When previously you could find diamonds in the rough in free agency and the draft, now those benefits appear to be sliding toward the 4-3 teams.
While there are still more 4-3 teams in the league than 3-4, because most college programs run some form of the 4-3 there are more players available throughout the NFL who fit in the 4-3 scheme. Instead of fighting over the minority, 4-3 teams can now pick out the best from the majority.
This year's free-agency class reflects this.
Arguably the leading free agent available, discounting Drew Brees because he will likely be tagged, Mario Williams won't be returning to Houston with the Texans because he is too big to play in a 3-4 defense.
Williams, along with John Abraham, Cliff Avril, John Abraham, Robert Mathis, Juqua Parker, Jeremy Mincey and Andre Carter, is part of a very deep 4-3 defensive end class on this year's free-agent market.
The New England Patriots were the first team to look to take advantage of this trend in the NFL when they acquired Andre Carter, Mark Anderson and Shaun Ellis last year. While the whole transition from a 3-4 to a 4-3 defense wasn't completely successful, largely due to the lack of impact from Albert Haynesworth and a horrible secondary, Bill Belichick did get quality play from previously written-off players.
In particular, Andre Carter, who had been overlooked in Washington when they implemented Jim Haslett's 3-4 scheme, found new life in Boston. Carter had 10 sacks in 14 games after just 2.5 with the Redskins the previous season.
Defensive end isn't the only position favoring 4-3 teams entering the 2012 free-agency period.
There are no elite tackles available, but Rocky Bernard just played a valuable part in winning the Super Bowl, and guys like Jason Jones (who can play both end and tackle), Brodrick Bunkley, Anthony Hargrove and Pat Sims have all got experience playing tackle in the NFL.
The inside linebacker position is led by the same free agent who led last year's group. Stephen Tulloch had a good season in Detroit, while Curtis Lofton, D'Qwell Jackson, David Hawthorne, Dan Connor, E.J Henderson and Barrett Ruud have all been starters.
Jarrett Johnson may have played his career in a 3-4 base in Baltimore, but he is versatile enough—and has played there for the Ravens at times—to be a starting 4-3 outside linebacker. Along with DeAndre Levy, Leroy Hill, Jo-Lunn Dunbar, Bryan Thomas, Manny Lawson and Geno Hayes, there are plenty of options for teams to fill out a 4-3 defense.
While those players aren't reputable names or stars for the most part, they are valuable role players who could come in and start on plenty of NFL defenses.
Of the 32 NFL teams, 11 were initially projected to have at least $20 million to spend in free agency. Eight of those 11 play 4-3 defenses, and they all have areas that need upgrading.
The Cincinnati Bengals were initially projected to have around $45 million to spend on potential new additions. For a team like the Bengals, their front seven already has a lot of talent. However, the prospect of adding a pair of defensive ends, whether it be Mario Williams and Cliff Avril, John Abraham and Robert Mathis or just one of those previously mentioned, should be mouthwatering to their fans.
Defensively, the strength of this free-agent class resides at 4-3 defensive end and cornerback.
As the New York Giants proved this past season, having talent at defensive end in a 4-3 goes a long way to having a strong overall defense. The Giants linebackers weren't stars—in fact, one of their starters was a defensive end in Mathias Kiwanuka.
However, the trio of Michael Boley, Kiwanuka and Chase Blackburn were good enough complementary pieces to take advantage of the quality upfront. That trio isn't hugely better than a group made up of say Barrett Ruud, Jo-Lunn Dunbar and Manny Lawson. Those three free agents won't cost much to bring in in free agency this year.
Essentially, if you already have quality at defensive tackle, such as the Cincinnati Bengals or the Buffalo Bills, who figure to have the best defensive tackle pairing in the league next year, you can build your whole front in free agency this year.
Building through the draft is generally the way teams sustaining success are formed, however when the quality is available in free agency like it is this year, there is no harm in going against that method.
Especially not in this year's offseason.