Marlon Lucky and Cody Glenn no longer are young pups in the Nebraska football program.

They know the playbook by now. Know their way to class. Know all that’s required to excel at the Division I level.

As the two I-backs prepare for their junior seasons, Husker running backs coach Randy Jordan hopes they feel a sense of urgency.

“The big thing I’m telling both of those guys is, you’re going into your junior year, man, and before you blink, the (2007) season will be over and all of a sudden you’re a senior,” Jordan said Friday. “You have to take advantage of every opportunity you get, and I think they realize that, especially after Brandon left.”

Jordan referred to Brandon Jackson, Nebraska’s rushing leader last season, who left school with a year of eligibility remaining to enter the NFL Draft. With senior Kenny Wilson sidelined this spring with a staph infection, Lucky and Glenn are easily the most experienced I-backs in spring camp.

“All of a sudden, when Brandon left, there’s a spot they’re going to have to fight for,” Jordan said. “There’s something about competition, and I think those guys are working extremely hard now to put themselves in a good situation.”

The 6-foot, 210-pound Lucky appears to have the inside track to the starting position.

“He wants to be the guy, and I’m challenging him to be the guy,” Jordan said.

Jackson rushed for 989 yards last season, including 835 after supplanting Lucky as starter in the week leading to the sixth game. Lucky finished second on the team with 728 rushing yards and fourth with 32 receptions (for 383 yards). Meanwhile, Glenn wound up with 370 rushing yards despite being slowed by injuries throughout the season.

A 6-foot, 230-pound native of Rusk, Texas, Glenn has been slowed by a foot sprain since Nebraska’s 11th game last season, a one-point win at Texas A&M.

Nebraska head coach Bill Callahan said Glenn’s straight-ahead running is fine; it’s cutting on the run that’s difficult.

Said Jordan on Friday: “Cody looks good. He’s finishing (runs). He’s not where he wants to be in terms of his conditioning because he hasn’t really done a lot. He’s making it through. Hopefully by the end of spring, you’ll see a healthy Cody Glenn, which I’m excited to see.

“I want to see the old Cody Glenn, the one we saw at Iowa State,” Jordan added, referring to Glenn’s 148-yard, two-touchdown rushing performance last October. “If we can get him back to that point, I think our running back situation — with the guys we have coming in — I’m really confident we’ll be OK.”

Nebraska has two other healthy I-backs for spring practice — sophomore Major Culbert, who played safety most of last season; and true freshman Marcus Mendoza, who graduated from high school at mid-year. Two other 2007 signees, Quentin Castille and Roy Helu, will join the fray this summer.

However, the young I-backs likely will be chasing Lucky. He apparently has recovered well from an unspecified medical emergency that left him hospitalized for four days in February.

Jordan said he has challenged Lucky to be an all-purpose I-back.

“Marlon is a fighter,” the coach said. “He’s working extremely hard, just like everyone else. He’s got a great attitude. I’ve probably gotten closer to Marlon over the last couple months than I ever have. I appreciate what he is and what he’s going to bring to this team.

“I think you’ll see a guy who’s going to smile more, a guy who’s going to play extremely hard every opportunity he gets.”

Meanwhile, Culbert — a 2,000-yard rusher as a senior in high school — has worked hard to refine his running back skills despite being recruited as a defender. Jordan said the 6-foot, 210-pound Culbert, of suburban Los Angeles, is unselfish and hard-working.

“One thing I like about him is his bottom end reminds me a little of myself when I played,” said Jordan, who enjoyed a nine-year NFL career. “I love those guys like Cory Ross and Emmitt Smith and Barry Sanders. They’re bottom heavy. Major’s got great lowers. He has good vision. He can read blocks fairly well. And he’s extremely hungry to learn the offense.”

Could Culbert wind up at I-back on a permanent basis?

“It’s too soon to say,” Jordan said. “We still have a lot of evaluation days in terms of spring ball. We haven’t even padded up yet. Until the live bullets start flying, that’s when I’ll be able to assess him as a running back a little bit more. But so far, he’s doing a fabulous job.”

The 5-10, 185-pound Mendoza also has drawn praise from coaches for his speed, explosiveness, open-field moves and soft hands.

What’s more, “It makes his learning curve a lot easier when you have veterans helping him,” Jordan said. “I’m real excited about this group.”

Briefly

Nebraska on Friday went through its second practice of the spring season, a two-hour workout in shorts and helmets inside Hawks Championship Center. The Huskers resume drills today.

Reach Steven M. Sipple at 473-7440 or ssipple@journalstar.com.