Dave Weaver, Associated Press
Nebraska football coach Bill Callahan has five games to prove to administration why he should remain the coach for the 'Huskers.

LINCOLN, Neb. — Bill Callahan has five games to prove to Tom Osborne why he should remain Nebraska's football coach.

That's the bottom line after Steve Pederson, the man who hired Callahan in 2004, was fired and replaced this week by the Hall of Fame coach and leader of the Cornhuskers' dynasty of the mid 1990s.

"I look at it as an opportunity," Callahan said. "That's just me. I'm optimistic."

Callahan is 26-18, with last year's run through a mediocre Big 12 North his greatest achievement.

The Huskers earned their highest ranking under Callahan at No. 14, after starting this season with two wins. But lopsided losses to Southern California, Missouri and Oklahoma State and a one-point win at home over Ball State have left the Huskers 4-3 and 104th nationally in defense entering Saturday's home game with Texas A&M.

Osborne's initial assessment?

"We'd like to see the intensity level pick up to what we're accustomed to," he said.

Osborne said he'll make a decision on Callahan after the season.

If Osborne chooses change, the next coach would be secure in knowing he's "Osborne's guy," a title that should come with the tacit approval of Husker Nation.

Also, Osborne's status might help draw more prominent candidates than the last coaching search did.

After Frank Solich was fired in 2003 by Pederson, potential candidates such as Florida coach Urban Meyer, then at Utah, avoided Nebraska. After all, if a coach can get fired after going 9-3 and 58-19 in six seasons, the margin for error must be razor thin.

If Callahan is let go, some of the potential candidates that have already been talked about include LSU defensive coordinator Bo Pelini, Buffalo coach Turner Gill and Wyoming coach Joe Glenn.

Pelini is on the short list of hot assistants in college football these days. He was hired by Solich as Nebraska's defensive coordinator in 2003 and proved extremely popular. He was interim coach for the 17-3 Alamo Bowl win over Michigan State, and as he walked off the field Nebraska fans chanted "We want Bo." Pederson interviewed Pelini, but Pelini said he never was given the impression he had a chance.

Gill is the former Nebraska quarterback of the early 1980s. Another popular figure in Huskers lore, he was a longtime assistant under Osborne and Solich and interviewed for the head coaching job in 2003. Callahan retained Gill as receivers coach, but Gill left after the 2004 season.

Glenn has built Wyoming into a Mountain West contender in his five seasons with the Cowboys. Glenn, who has won national titles at the Division I-AA and II levels, is a Lincoln native.

University chancellor Harvey Perlman has said the football program was in "disarray," and the 70-year-old Osborne promises to stay as long as necessary to put the house in order.

"My intention is to work myself out of the job," Osborne said. "I would hate to speculate on the number of months or years or whatever it may be."

His first task is to get to know Callahan.