LINCOLN, Neb. -- Nebraska athletic director Steve Pederson was fired Monday, two days after the school's once-mighty football team was rocked with its worst home loss in nearly a half-century.

Pederson, along with coach Bill Callahan, has been heavily criticized after a series of one-sided losses this season. The most recent was a 45-14 loss to Oklahoma State on Saturday with former Cornhuskers coach Tom Osborne and his 1997 national title team in attendance.

Callahan's job is apparently safe for now. Chancellor Harvey Perlman said the next athletic director would decide the fate of the football staff.

Over the past two weeks, the Huskers (4-3) have lost by a combined score of 86-20, dropping a 41-6 decision at Missouri two weeks ago.

"There is no joy in my heart for having to do this," Perlman said. He said it would cost at least $2.2 million to buy Pederson out of his contract.

At the end of the July, Pederson's contract was renewed for five years, but this season has been a nightmare for the most part. Even in victory -- a 41-40 nail-biter against Ball State -- the Huskers' defense was far from the force it used to be.

For the first time in their 118-year history, the Cornhuskers have allowed at least 40 points four times in a season.

"You make the best decision you can with the information you have," Perlman said.

The chancellor also said since July he's noticed a decline in morale and growing concern about keeping key personnel in the athletic department. Paul Meyers, a key fundraiser, was among several people who departed.

Several people came forward with concerns about Pederson's management style and his connection with staff, donors and athletes, Perlman said.

"Every one of you thinks this is because of a football game that was played last Saturday," Pederson said. "It may well be that the vulnerability of the football program encouraged people to come forward when prior to that they had not."

A search for an interim athletic director has begun, with the next step to find a permanent replacement.

"It is not clear how long such a process will take or its precise form," Perlman said. "It is important it be done expeditiously but thoughtfully."

Perlman said he would consult with Osborne about the direction of the athletic program, but stopped short of saying he would offer Osborne the interim athletic director's job. Osborne now teaches a business leadership course at the university and is a consultant to local college athletic programs.

Callahan, who signed a five-year contract last month, said less than two hours before Pederson's firing that they talked almost daily about the program.

"We've come under a steady stream of criticism," Callahan said. "It's important you stand tall. You'll be the direct target of critics. I understand that. You're in the public eye and in a high position in order to lead. We're going to continue to lead in a very positive manner."

In four seasons under Callahan, the Huskers are 26-18 overall, 14-14 against the Big 12, 3-8 against teams in the Top 25 and 0-6 against the top 10. They have given up 40 points or more nine times.

Pederson has been a polarizing figure in Nebraska, widely criticized for firing coach Frank Solich and then for conducting a protracted one-man search for a new coach.

Pederson may have been his own worst enemy, setting the bar high for Callahan and raising fans' expectations.

"I refuse to let the program gravitate into mediocrity," Pederson said the day he announced Solich's firing. "We won't surrender the Big 12 to Oklahoma and Texas."

Despite firing a coach with a 9-3 record that season and a 58-19 career mark, Pederson said he was not running a "win at all costs" program.

He said he did not like the direction the program was taking after going 16-12 in Solich's last 28 games.

"The byproduct of excellence in every area of your program is winning, and I don't apologize for having high expectations," Pederson said.

"This is the best job in the country, and anyone who doesn't want to win the national championship shouldn't bother applying for this job. I understand we aren't going to win the championship every year, but I believe we should be playing for or gaining on the championship on a consistent basis.

Pederson had at least four candidates turn down the job before he hired Callahan, who had just been fired by the Oakland Raiders.

The Huskers went 5-6 in Callahan's first season but improved to 8-4 in 2005. They were 9-5 last year, winning the Big 12 North and losing to Oklahoma in the conference title game. They then lost to Auburn in the Cotton Bowl.

Any traction gained last year had been lost this season.

Pederson, who grew up in North Platte, Neb., and worked at Nebraska in the sports information office and football program, was athletic director at the University of Pittsburgh when Nebraska hired him in 2003.

"The selection of Steve Pederson in 2003 as athletic director was widely thought to be the only clear choice because of his experience, his roots and his knowledge of our traditions," Perlman said. "I know Steve made the decisions he thought best for the interests of the program and the university. I am disappointed that I had to come to this decision."

Steve Glenn, a Nebraska offensive lineman in the late 1970s, said the firing of Pederson is "the best thing to happen to Nebraska football in 10 years," adding, it "lifts a cloud off the state of Nebraska."

Glenn said he hoped Osborne, 70, would take the interim AD's job.

"What a great man of integrity -- he could do great things for the university," especially if the team has to recruit a new coach, Glenn said.

Osborne didn't immediately return a phone message Monday afternoon.

"I don't know whether the lynch mob is going to be satisfied with one body," said regent Randy Ferlic, who added he and other regents have received hundreds of e-mails calling for the firing of Pederson, Callahan and Perlman.

Ferlic said he worried the decision sends the message that a few fans can get a ball rolling and get people fired.

Copyright 2007 by The Associated Press