San Diego Chargers GM A.J. Smith often says he believes in the adage "defense wins championships." And he's backed it up with his drafting. In the last five years, the Chargers have used five first-rounders on defensive players, and they've made the playoffs every year since 2006.
But he has no Super Bowl ring.
It's easy to be fooled by the adage, because almost every championship team from the last 20 years has had a good, if not great, defense. In addition, the numbers show that teams win more when they heavily invest first-round picks in defense.
But, despite these arguments, defense can take you only so far. And as the spread offense in college football makes scouting tougher for NFL clubs, we may soon be saying "offense wins championships."
DEFENSE WINS GAMES
Devoting several first-round picks to defense will generally yield more regular-season wins.
We looked at every team from 1994 to 2009 and analyzed how they used their first-round picks in the previous five seasons. It turns out, teams that selected five or more first-round defenders won an average of 8.8 games a season.
"Drafted D" is the numbers of defensive players a team drafted in the previous five years.
Another reason to draft defense in Round 1 is that, with the emergence of the spread, offensive players are becoming harder to project. NFL Network draft analyst Mike Mayock told SI.com, "NFL guys I talk to on a daily basis are getting frustrated, and I'm like, 'Too bad, guys, because that spread offense is not going away.'"
You would think that, because of this uncertainty, teams are shying away from drafting offensive prospects. But that hasn't been the case.
In every five-year era (i.e. 2005 to 2009) in the last 20 years, almost exactly 50 percent of first-round picks are on defensive players, and 50 percent are offensive players.
Even as confidence in offensive prospects drops, the rate at which they are drafted in Round 1 is staying the same. This means more unknown commodities are sneaking into the first round.
The solution seems clear: draft more defense in Round 1.
But, of course, the silver bullet is more elusive than that.
Ten years ago, Oakland Raiders owner Al Davis must have heard the phrase "defense wins championships." Starting in 2001, he drafted seven first-round defenders in six years -- the most in NFL history. But by the time he was done in 2006, the Raiders were 2-14 with a mediocre defense and a horrendous offense.
They were somewhat of an anomaly -- the other 29 teams that took five or more defensive players in the previous five years averaged an astounding 9.4 wins. But the Raiders also showed that hoarding first-round defenders is not a one-step formula for success.
To invest so heavily in defense, teams must first have a solid offense and a strong scouting staff to replenish the offense. In short, it's a luxury to be able to add four or five first-round defenders in five years -- something Al Davis couldn't afford. In fact, only two teams in the last 20 years were able to invest so heavily in defense and still win a Super Bowl: the 1994 49ers and 1995 Cowboys -- both offensive juggernauts.
So although heavy investment in defense will win you games, it won't win you a championship.
OFFENSE WINS CHAMPIONSHIPS
A few recent champions are rewriting the way Super Bowls are won. From 1990 to 2006, every Super Bowl winner had a top-10 defense. But since then, the Colts, Giants and Saints won it all with statistically below-average defenses.
The defensive rank of the team is determined by points allowed, and it reveals that many recent champions have not had great defenses.
In addition, Super Bowl champions since 2005 have used fewer recent first-round picks on defensive players; they chose to help their offenses slightly more, but they remained mostly balanced. And that has been key because, historically, teams that neglect one side of the ball rarely win Super Bowls.
In the spread era, several other strategies will come into play as some teams will focus on defense to avoid the uncertainty of offensive players. As we've shown, however, it's hard to win a championship this way unless you already have a great offense.
So inevitably, teams will have to figure out how to scout offensive prospects. And if the Colts and Saints are any indication, the new mark of a champion might be offensive firepower -- they will be teams that try to outscore everyone because they believe the best offenses are generally better than the best defenses.
This means that whatever teams find the best way to evaluate prospects from a spread offense may find themselves with a few Super Bowl rings, and perhaps they'll earn credit coining the phrase "offense wins championships."
Alvin Chang is a contributor to ESPN Insider. Check his online archives here. Trevor Ebaugh of ESPN Stats & Information also contributed to this article.