INDIANAPOLIS -- Maybe it was symbolic that, in recently addressing his role with the Super Bowl champion Indianapolis Colts for 2007, second-year tailback Joseph Addai chose to plant himself atop a large storage chest in a hallway just outside the locker room.
The ponderous metal shipping locker, painted in Colts colors, is used to carry heavy loads to road games. And Addai, who led all rookies in rushing yards in 2006 despite not starting a regular-season game, also figures to tote a significantly heavier load in the offense this year.
Dominic Rhodes, the nominal starter in 2006, is gone, having defected to Oakland as an unrestricted free agent. The remaining depth chart, at least for now, includes an unproven back claimed on waivers last season, two college free agents from Harvard and Indiana University of Pennsylvania and a guy who played the past four seasons in the CFL.
Total regular-season carries for the quartet: zero.
But the Colts' brass doesn't appear overly concerned, and Addai certainly isn't daunted by the prospect of a more ambitious workload. "We're confident that someone will step up from that bunch of guys," coach Tony Dungy said at last weekend's minicamp.
"I haven't changed anything in terms of preparation," said Addai, who slid into the starting lineup at the outset of the playoffs and finished No. 3 in rushing yards and No. 1 in receptions in the postseason. "When I went to camp last year, I approached it like I was going to be the starter, and I'm going in the same way this year. So it's no different. I mean, Dom was a great guy to have around and we got along really well, and he'll definitely be missed. But I don't want to make too big a deal about the fact he's gone now."
It is notable, however, that less than four months after the Colts became one of the few teams to win a Super Bowl while implementing a tandem approach at tailback, the supposed hot trend already may be waning.
There an old NFL adage that you can never have enough good running backs. But right now, some teams, including a few presumptive title contenders, are staring at depth charts weakened by offseason attrition.
Just when it seemed the pendulum was swinging toward teams that preferred a two-back system, a practice that would have been anathema not too many years ago, the momentum seems to have shifted again. General managers who were justifiably concerned over the effects of wear and tear on their No. 1 tailbacks, and thought that they had found a viable solution by spreading the carries around, suddenly find themselves fretting again about a lack of distribution in the running game.
Seven teams in 2006 featured two tailbacks who each logged 125 carries or more and who also posted more than 575 yards apiece. From that group came all four franchises in the two conference championship games. But now three of those teams -- Indianapolis, Chicago and New England -- will enter the 2007 season without their tailback duos of a year ago. In addition to Rhodes' exit, the Bears traded starter Thomas Jones to the Jets and New England released Corey Dillon.
From among last year's conference finalists, only New Orleans, which still employs Deuce McAllister and Reggie Bush, returns for 2007 with the top two spots on its tailback depth chart unaltered. Of the other eight playoff teams from a year ago, half still must address varying degrees of uncertainty or instability at the No. 2 tailback spot.
"There's been a lot of movement at the position, starters and key backups, definitely," said New York Giants coach Tom Coughlin, whose top runner, Tiki Barber, retired. "It's really not a position where you want to get caught without enough [bodies]."
Proponents of the shared-backfield paradigm point out that there remain some excellent tailback tandems in the league -- Fred Taylor-Maurice Jones-Drew in Jacksonville, Julius Jones-Marion Barber of Dallas, Clinton Portis-Ladell Betts in Washington, San Diego's LaDainian Tomlinson-Michael Turner pairings among them. But there are enough high-profile teams that have suddenly been weakened at the position that the problem definitely is magnified.
The offseason shakeup means that Addai, fellow second-year veteran Laurence Maroney of the Patriots and the Bears' Cedric Benson, like the other two a former first-round selection, are left as starters for their respective 2007 conference finalist teams. And while all three teams are confident in their young starters, they are also left with some holes.
Chicago will rely on five-year veteran Adrian Peterson, known mostly as a standout special-teams performer, to buttress Benson. The former Georgia Southern star has never carried more than 76 times in a season. Jones averaged 283.3 rushes in his three years with the Bears. The Patriots still have third-down specialist Kevin Faulk, but he has just 130 carries total the past three seasons after posting a career-best 178 rushes in 2003, and is a better receiver than runner. New England did sign seven-year veteran Sammy Morris, but despite 132 carries in 2004, his career average is 53.4 attempts. Dillon owns a career average of 261.8 rushes and in 2006, even at age 32, he registered 199 carries.
Complicating the situation in New England is that Maroney is battling a shoulder problem from last year.
A plus for Indianapolis is that it has a healthy Addai, 24, ready and eager to assume an expanded role, if necessary. The great unknown, however, is how Addai will respond late in the season if the Colts ask him to carry the ball 20 times a game.
Still, despite not starting in the regular season a year ago, Addai finished nine games with more carries than Rhodes, and 11 times he registered more touches from scrimmage. His 226 carries and 266 touches during the '06 season were his most since he played at Sharpstown High School in Houston. He notched 76 carries in Indianapolis' four-game playoff run and, extrapolated over a 16-game schedule, that would come to 304 rushes for the year. Counting the playoffs, Addai had 302 carries in 20 games last season.
Even during his four college seasons, Addai was more quarter horse than workhorse, and he never got 200 carries or 1,000 yards in a season because of the always well-populated LSU backfield. Addai averaged just 120.5 attempts for his career and didn't have more than 114 rushes in any season until his senior year. That final season was the lone campaign in which Addai touched the ball more than 200 times.
"But just because no one has asked me to do it, doesn't mean I can't do it, if asked," Addai said. "I'm a little stronger, maybe five pounds more than I was a year ago, now that I've been in the weight program here. I definitely know the game a lot better.
"The biggest thing for me has been learning how to 'unthink' in this second season. When you're a rookie, even at a skill position like [tailback], you're still thinking about everything, and it slows you down. Most stuff comes a lot more naturally now, I'm noticing, so I don't have to think every little detail through. Now I'm just concentrating on showing people that I can be an even better player than I was [in 2006]."
Len Pasquarelli is a senior writer with ESPN.com.