The first head-coaching dismissal of the season came yesterday, as the Detroit Lions fired Steve Mariucci four days after a pitiable showing in a Thanksgiving day loss to the Atlanta Falcons dropped the team to 4-7.

The Lions made defensive coordinator Dick Jauron their interim coach.

Mariucci was in the third season of a five-year, $25 million contract. The Lions are 15-28 since club president Matt Millen abruptly dismissed former coach Marty Mornhinweg to hire Mariucci in 2003. Millen was so eager to get Mariucci that he violated the league's rule requiring each team with a coaching vacancy to interview at least one minority candidate, and ended up being fined $200,000 by NFL Commissioner Paul Tagliabue.

But Millen said during a news conference yesterday that "it didn't work." Millen said he accepts his share of the blame but believes that the Lions -- after using first-round draft choices over the past four years on quarterback Joey Harrington, tailback Kevin Jones and wide receivers Charles Rogers, Roy Williams and Mike Williams -- have the talent to be a playoff contender.

"We started off this season with high expectations," Millen said. "I thought, and I still think, this was a roster capable of making a playoff run. Quite frankly, I believe we've underachieved as a football team and I believe we have not developed our younger players, and that's bothersome. . . . The talent is there, and we have not played up to that talent."

Millen said he was angry after Thursday's 27-7 defeat to the Falcons but didn't make a decision about Mariucci's status until early yesterday after "lengthy discussions" with members of the Ford family, the team's owners. The Lions also fired two of Mariucci's assistants, offensive line coach Pat Morris and tight ends coach Andy Sugarman, and promoted Greg Olson from quarterbacks coach to offensive coordinator.

Millen said that Jauron, head coach of the Chicago Bears from 1999 to 2003, was given no promises about getting the job permanently and the Lions' coaching search will comply with "all applicable NFL guidelines." Jauron said his initial reaction was not to take the job, but he relented after consulting with his family. "I don't think anyone in the league likes this situation, but it's where we are," Jauron said. "We need to take these next five games and play and see what we can get out of it."

McNabb Has Surgery

Philadelphia Eagles quarterback Donovan McNabb underwent abdominal surgery yesterday.

The procedure was performed by William Meyers of Drexel University, one of the specialists who recommended in recent weeks that McNabb not put off the operation on his sports hernia until after the season. According to Eagles Coach Andy Reid, McNabb was told to stay off his feet for the next three weeks. The club already had placed McNabb on the injured reserve list, ending his season.

The Eagles signed 43-year-old punter Sean Landeta. He replaces Nick Murphy, who was released, and becomes the Eagles' fourth punter this season. Quarterback Andy Hall also was released to create a roster spot for deactivated wide receiver Terrell Owens, whose four-game suspension ended yesterday. . . .

The Dallas Cowboys placed linebacker Dat Nguyen on the IR list, ending his season, and signed veteran linebacker Michael Barrow.

Lions President Matt Millen, right, turns head coaching duties over to former defensive coordinator Dick Jauron, left, after firing Steve Mariucci.