Is this guy more important to Purple Jesus than Purple Jesus himself? Getty Images


It's the NFL's ultimate chicken-or-egg question, and it extends far beyond Saturday's draft. Simply put, what's more important to a successful running game, the running back or the offensive line?

Of course, there's nothing simple about the question, which is why consensus is just as tough to find among experts as with bar-stool GMs. That couldn't have been more clear after talking to a pair of current personnel men (Minnesota's Rick Spielman and Buffalo's John Guy), one of their former cohorts (ex-Titans GM Floyd Reese) and two analysts who once played on each side of the debate, my ESPN colleagues Mark Schlereth (lineman) and Merril Hoge (running back).

Spielman, Reese and Hoge opted for the running back. Schlereth (shockingly) and Guy went with the line. Now, I'm not saying the RB trio is wrong. I'm just saying the other guys were a lot more convincing, especially once I threw some stats into the mix.

Oddly, one of the few areas where everyone agreed helped settle the debate. They all made an exception for the so-called "special" back. Spielman says this specimen can turn an average O-line into a good one by setting up blocks. Hoge says these guys "hit home runs" in the open field. Even Guy says they "do a lot on their own."

Sweet. I'll take one for my team, thank you. Just tell me where to shop. What's that? Apparently there's only one in stock, and he currently resides in San Diego? Well, that changes things. LaDainian Tomlinson is the only RB each expert put in that "special" class. Everyone else -- Larry Johnson, Shaun Alexander, Steven Jackson, Frank Gore, even Reno Mahe -- couldn't earn a universal greatness tag. Hoge puts Adrian Peterson in that class. We'll see.

So, short of finding the next LT or Barry Sanders, what's the best plan? Hoge knows: "I've always believed if you build closest to the ball first and you're solid there, all your skill players will be that much better."

Why? Allow Schlereth to explain: "The initial push has to be there for any running back," he said. "After you break that initial hole, that's when the special nature of a back comes through. But if you don't have something up front instantly, you're in trouble."

Makes sense to me, Mark. So, please carry on. After all, you did play for a Denver team that kept plugging in guys off the street for 1,200-yard seasons. "Last year, everybody's pick to win the NFC was the Carolina Panthers," Schlereth said. "Then they lost two offensive linemen in the first week of the season."

And they waved bye-bye to the playoffs. The Panthers weren't the only elite team to suffer the effects of O-line attrition. Seattle lost Steve Hutchinson through free agency, battled injuries along the line all season, and ended up finishing 9-7. Sure, Alexander missed six games, but he averaged 1.5 yards per carry fewer than in 2005 and was already struggling before injuring his foot. Meanwhile, Hutchinson's new team, Minnesota, suddenly improved from 27th to 16th in rushing.

Then there are the Jets. A year after their aging line finally crumbled, they grabbed D'Brickashaw Ferguson and Nick Mangold in the first round of the 2006 draft. Despite a three-headed RB committee of nobodies, New York improved from second-worst in rushing to 20th, finished 10-6 and made the playoffs.

That's not to say that a successful line has to be a collection of first-round picks. The key -- and all five experts agree -- is continuity. And that's where the stats come into play. Consider:

Over the past five years, 32 teams have either risen or fallen at least 15 places in rushing from one season to the next. Digested that? Good. So, I studied the lineups from both the "good" year and the "bad" year. Guess what? 75 percent of the time, the "good" year was the season in which the O-line was healthier.

Of the 20 starting lines from the past 10 Super Bowls, 11 had all five players who started the previous season. Six other groups had just one new face. Only the 2000 Giants -- perhaps the weakest of the bunch -- reached the Super Bowl with a line that had three newcomers (the immortal trio of Lomas Brown, Glenn Parker and Dusty Zeigler).

Of those Super Bowl O-lines, almost as many undrafted free agents (21) started as first-round picks (27). There were more seventh-rounders (12) than second-rounders (five). "Scheme" goes hand-in-hand with line play, and lines like the Colts, who started two undrafted guys in the Super Bowl (Jeff Saturday and Ryan Lilja), a fifth-rounder (Jake Scott) and a fourth-rounder (Ryan Diem), develop continuity within a system over time. As Schlereth puts it, "I've always said we could all be doing the wrong thing, but as long as we're doing it wrong together, odds are we have a pretty decent play."

Wait, does keeping a bunch of afterthought blockers together for a couple of years really beat picking up a 1,500-yard runner? In a word: yeah. Or, in two words: Edgerrin James. You remember what happened to Edge this year, right? It was called the Arizona line. After rushing for 1,506 yards and 4.2 yards per catch with Indy in 2005, he plunged to 1,159 yards and a career-low 3.4 ypc behind a line with more holes than the plot of "24." His longest run was 18 yards. Ouch. Meanwhile, his replacements in Indy -- Joseph Addai and Dominic Rhodes -- combined for 1,742 yards 4.2 ypc (sound familiar?).

Edge isn't the only runner to face the free-agent flip. Over the past nine seasons, 22 starting or time-share RBs switched teams and retained a featured role. And of the three parties involved (the RB, his new team, and his old team), most of the time it was the running back whose stats changed significantly (at least half a yard per carry). Put another way, teams were more stable from year-to-year than one player.

That's tough evidence to refute. Still, maybe Reese is right when he says he'd grab a back first, then create the right line to support him. Maybe Spielman's experience in Detroit with Barry Sanders, which leads him to say, "A great running back makes a great offensive line," has merit. Heck, even Schlereth says that when Olandis Gary rushed for 1,159 yards in 1999, Terrell Davis would have gone for 1,600.

But few, if any, backs are of the Sanders/Davis caliber. And that's why systems like Denver rule, where well-schooled, cohesive lines pave the way for a myriad of runners. Kansas City has enjoyed similar success -- Priest Holmes, Derrick Blaylock and Larry Johnson proved that point in 2004. But that trend could be dying. LJ averaged 5.2 ypc in 2005. Last year, Willie Roaf retired and that average fell to 4.3. Now, stalwart Will Shields is gone. Schlereth says of Johnson, "I guarantee he's not going to be what he once was."

Still, someone's going to grab Peterson early in the draft tomorrow, hoping for a quick fix for a stale running game. Hoge says Peterson is as good an open-field runner as he has seen in eight years of playing and 10 years of studying film. He added that Peterson finishes his runs like Walter Payton. "I'd take him right now," Hoge says. "Whatever my line is right now, he'd make it that much better." Hoge had better be right. Otherwise, a mediocre line is about to make Peterson look a lot worse.