Nebraska is shuffling the deck at its linebacker positions but holding firm at cornerback in the wake of two season-ending knee injuries incurred Saturday.

Lance Brandenburgh will move from his top backup spot at strongside linebacker to middle linebacker behind starter Corey McKeon, Husker coach Bill Callahan said Monday. 

Brandenburgh, a junior, has experience at middle linebacker, having practiced there throughout preseason drills last year before moving to weakside linebacker early last season and finishing 2005 in that spot. He switched to the strongside position this past spring.

Meanwhile, sophomore Clayton Sievers, who has become a key two-way player, will fill Brandenburgh’s role as backup at strongside linebacker behind starter Stewart Bradley, Callahan said. The coach indicated Sievers already has been practicing there at times.

The position moves are in response to No. 2 middle linebacker Phillip Dillard’s season-ending torn anterior cruciate ligament suffered in Nebraska’s 49-10 win against Louisiana Tech on Saturday at Memorial Stadium.

“Phillip was having a heck of a game,” Callahan said. “He had a terrific preseason camp. I thought we were going to see great things from Phillip. It’s just painful to see a guy of his caliber go down early in the year.”

Isaiah Fluellen, a senior cornerback, also suffered a season-ending ACL injury against Louisiana Tech, Callahan confirmed. The 6-foot, 190-pound Fluellen, listed No. 2 on the depth chart behind junior college transfer Andre Jones, was injured in the second quarter on his first play from scrimmage.

Fluellen had moved from wideout to cornerback Aug. 7, two days after senior starter Zackary Bowman suffered a season-ending torn ACL. Callahan said there are no plans to move any other players to cornerback.

“Isaiah had made a wonderful transition — a quick transition — to the defensive backfield,” Callahan said. “He has tremendous skill and speed and was plugging in nicely. We’re just going to have to have more guys step up.”

Junior Cortney Grixby, playing with a hard cast on his right hand to protect a broken thumb, entered this season as the only Nebraska cornerback with starting experience in college. Other backup corners prominent in the Huskers’ mix are juniors Titus Brothers and Tyrell Spain (also a converted wideout), as well as true freshmen Anthony West and Corey Young.

As for the linebacker positions, Brandenburgh and Sievers are accustomed to change. The 6-1, 230-pound Brandenburgh, who has 26 career tackles, has spent significant blocks of time at each of the three linebacker positions during his Nebraska career.

This past spring, Husker defensive coordinator Kevin Cosgrove said Brandenburgh, in an ideal world, would probably be best-suited for middle linebacker.

The 6-4, 240-pound Sievers, an Elkhorn native, saw action on both sides of the ball against Louisiana Tech, playing defensive end in the nickel package while entering the game as a tight end in short-yardage situations.

“I came out of high school as a two-way player,” Sievers said. “But I never thought I’d play both sides of the ball here. The coaches say they want to maximize my playing time.”

Sievers and Brandenburgh began focusing on their new roles Monday as Nebraska prepared for Saturday’s 12:30 p.m. home game against Division I-AA Nicholls State, which comes off a 35-0 home win against Southern Arkansas. The Colonels are ranked 16th in the latest I-AA poll after starting the season at No. 24.

Wise football men like to say a team typically makes its biggest jump in improvement after playing its first game. Callahan said the Huskers have plenty on which to improve before Game Two.

For instance, he said, there exist  “a number of things” in the special teams that need polish. Plus, he noted four dropped passes Saturday, a few costly penalties on offense and two turnovers in the red zone.

Nebraska’s offensive line — a primary area of concern entering the season among fans and pundits — showed improvement compared to 2005 in both run-blocking and pass protection, Callahan said.

However, “I came out (of Saturday’s game) very tempered,” he said. “I’m excited for the kids, but I know the (Big 12) conference is going to be the real challenging aspect of our schedule as we get deeper into it.”

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