DETROIT — Steve Mariucci was hired as coach of the Detroit Lions on Tuesday, taking over one of the NFL’s worst teams less than three weeks after his dismissal by the 49ers.

Mariucci, born and raised in Iron Mountain, Mich., signed a contract with the Lions and will be formally introduced at a news conference Wednesday, team spokesman Bill Keenist said.

Fired by the San Francisco 49ers after six seasons, Mariucci becomes the Lions fourth coach in four seasons. He replaces Marty Mornhinweg, who was fired last week after the Lions went 3-13. In two seasons, Mornhinweg was 5-27 — the worst two-year mark in team history.

Mariucci was 60-43 with the 49ers, and coached them to the playoffs four times. The 49ers were eliminated in the second round of the playoffs this season, losing to Tampa Bay 31-6.

Mariucci clashed with 49ers owner John York, and was dismissed three days after the loss to the Buccaneers on Jan. 12. His postseason record was 3-4 — the Lions have just one playoff victory since winning the NFL title in 1957.

Mariucci presided over a remarkably brief rebuilding period in San Francisco, but it wasn’t enough to save his job — even with a year left on his contract.

He was the loser in a battle of wills featuring York, general manager Terry Donahue and Hall of Fame coach-turned-adviser Bill Walsh — none of whom were around when Mariucci was hired in 1997.

The reasons for Mariucci’s departure were murky — perhaps by design for an organization that apparently felt Mariucci wasn’t the man to lead the young, talented team he helped build from scratch.

Mariucci’s flirtations with other jobs in the last offseason also didn’t engender feelings of loyalty from York.

“I think it’ll be good. Good for him, because he will be in a situation where he’s actually wanted and appreciated,” Lions defensive end Robert Porcher said Tuesday. “I think it’ll be good from a team standpoint because now our general manager gets the guy that he’s always wanted.

“And I think from the players’ standpoint, it’ll be excellent because he brings in that instant credibility with his winning record in San Francisco.”

This season, San Francisco went 10-6 and reclaimed the NFC West title before making the second-biggest comeback in NFL playoff history, to beat the New York Giants 39-38.

Mariucci repeatedly said he wanted to keep his family in the San Francisco Bay area, and he would be willing to take a minimal raise or even coach the final year of his contract without an extension.

He will be about 90 miles away from best friend Tom Izzo, Michigan State’s basketball coach. Mariucci and Izzo grew up together and attended Northern Michigan.

Mariucci has been Detroit’s leading candidate since the Lions fired Mornhinweg. Wednesday night and early Thursday, Mariucci became the only coach to have an in-person interview with the Lions.

Lions chief executive Matt Millen never publicly named any other candidate for the job ,but said the Lions would do their best to comply with the NFL’s policy of interviewing at least one minority candidate.

Mariucci agent Gary O’Hagan, also agent for former Minnesota coach Dennis Green, refused to comment on numerous reports that Green refused to interview with the Lions because they appeared to have their sights set only on Mariucci.

Attorneys Johnnie Cochran and Cyrus Mehri, leaders of a campaign for more minority hiring in the NFL, said in a Monday statement, “The Lions have seriously threatened to undermine and potentially violate the new NFL minority hiring policy approved by team owners in December.

“Prior to conducting a single interview, general manager Matt Millen essentially crowned Steve Mariucci as the Lions’ new head coach. He might well have put up a sign at Lions’ headquarters reading, ‘Head Coaching Vacancy: Minorities Need Not Apply.”‘

O’Hagan has said Mariucci’s ties to Michigan have played a part in his interest in the Lions after he initially said he would take next year off from coaching. Mariucci did not want to be considered in January for the opening in Jacksonville.

The Associated Press