8-23-07 - The Oklahoma Sooners have already experienced life without Adrian Peterson and it wasn't all that scary.

Sure it would've been great to have the third-leading rusher in school history back for his senior season, but the Sooners have a quintet of tailbacks lining up to take his place.

"No one can ever fill Adrian Peterson's shoes," said DeMarco Murray, a freshman who dazzled enough in the spring that coach Bob Stoops called him the team's best big-play threat at the position. "All you can do as the next guys is just step up. I think that's what we all have in mind. We're not worried about Adrian Peterson."

Peterson ran for 4,045 yards in his three-year career, including a school-record 1,925 yards as a freshman when he finished second in Heisman Trophy voting. He ranks behind only 1978 Heisman winner Billy Sims and Joe Washington in the Sooners' storied history.

But Oklahoma's running game never broke stride after Peterson broke his collarbone midway through last season. Allen Patrick, Chris Brown and Jacob Gutierrez filled in for Peterson admirably, combining for 1,149 yards as the Sooners won six straight games.

A year earlier, Patrick and Gutierrez took over after Peterson sprained his ankle -- and the Sooners won back-to-back games.

"I think we're 8-0 without him. So in the end, we're used to that," Stoops said. "That won't be a factor for us in how we run our offense."

Instead of focusing on how to replace Peterson, the Sooners have spent the months since their dramatic overtime loss to Boise State in the Fiesta Bowl determining the best quarterback among three unproven candidates: Sam Bradford, Joey Halzle and Keith Nichol.

Bradford earned the starting job, and he'll take control of an offense that returns mostly intact.

The entire receiving corps is back, along with two proven tight ends and four of the five starting linemen.

On defense, things aren't so clear-cut. Top tacklers Rufus Alexander and Zach Latimer are gone at linebacker, and the three top defensive ends have also moved on. The strength of the unit is a secondary that seems to be settling in after numerous position changes over the past two seasons.

But when the season opens Sept. 1 against North Texas, the Sooners' spotlight will be on the backfield. Coaches will be watching to make sure Bradford doesn't become prone to costly mistakes, and the same might be said at tailback after Oklahoma led the nation with 22 lost fumbles last season.

Stoops likes the concept of splitting time among the running backs, believing that none of the five shares the same physical prowess and stamina as Peterson, the No. 7 pick by Minnesota in April's NFL draft.

Patrick, a former defensive back, has shown he can outrun defenders and handle the starter's role. Brown has impressed with his consistency. Gutierrez has repeatedly excelled as a fill-in, including a 173-yard game in his first start.

Murray isn't the only freshman in the mix. Coaches also like Mossis Madu, who redshirted last season.

"There's a chance for us all to get out there. It's whatever coaches feel like, who's playing harder and stuff like that," Murray said.

The Sooners have enough talent stocked up at the position to be comfortable someone -- or some combination -- will come through.

The other challenge is finding the next star whose work ethic can he held up as an example to teammates. Coaches regularly touted Peterson as the team's top practice player, and his dedication remained on display as Peterson continued workouts in Norman during a brief contract holdout.

"To have a great team, your best players are held up high and there's a way they act and a way they practice that gives them a chance to maximize their talent," offensive coordinator Kevin Wilson said. "You can lift a great player up and say. 'Not only is he good but look at how he prepares. That's what it looks like. That's what it's about."'