The Detroit Lions had just finished going over their Friday install for their Week 1 game against the San Francisco 49ers, putting in short-yardage and red-zone plays, when Amon-Ra St. Brown turned to one of his teammates and asked of the assistant who just made the presentation: Who’s Ben Johnson?

“His attention to detail when he was installing these plays in the red zone,” St. Brown recalled in an interview with the Free Press last month. “He presents really well. He’s super confident up there. He knows what he’s talking about. You can just hear it in his voice. So I just remember him going up there, I think it was early in the year, installing red zone plays, and right from then on I knew he was a smart, special dude.”

The Lions hired Johnson as their new offensive coordinator Monday, finalizing a promotion three months in the making.

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Johnson, a Lions assistant the past three seasons and the team’s tight ends coach since 2020, takes over for Anthony Lynn, who was fired in January after having his play-calling duties stripped at midseason.

Johnson served as the Lions’ unofficial pass game coordinator the final nine weeks of the season, while head coach Dan Campbell called offensive plays.

The Lions won their only three games of the season during that stretch, increased their scoring by more than four points per game and showed significant improvement in a pass game that sputtered through the first half of the year.

Campbell has not yet decided if he or Johnson will call plays in 2022.

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Johnson, who served as offensive coordinator for the American team at the Senior Bowl last week, has never been a play caller at any level before. But the former walk-on quarterback at North Carolina is considered a creative play designer and earned high marks from Lions players for his ingenuity.

“He’s open to all new ideas,” said St. Brown, who caught 63 of his Lions rookie record 90 passes in the final nine games of the season. “So as a player, we love that. The quarterbacks love him. I think all the receivers, we all love him. So if he does get the job, I’m going to be super excited because without him I don’t think I would have had the numbers that I had toward the end of the year. I love Coach Ben.”

A self-described “math geek” in college, Johnson has coached a variety of positions and learned a number of systems since getting his coaching start as a graduate assistant at Boston College.

He spent three seasons with the Eagles and the past decade as an NFL position coach with the Miami Dolphins and Lions, where he worked with quarterbacks, receivers and tight ends.

He spent four seasons working with Campbell in Miami, and said last week his job as coordinator will be to implement Campbell’s vision for the offense.

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“I think it really kind of centers there,” Johnson said. “This is a head coach-driven team and that’s offense, defense and special teams, and where he wants it to go we will go and that of course depends on our personnel and goes out from there, and of course this time of year is huge in terms of personnel acquisition. So don’t know exactly what the offense will look like next year until we get those guys on our team.”

Campbell said during the Senior Bowl he would interview multiple candidates for coordinator, though Johnson always appeared to be the front-runner.

The Lions are expected to make an outside hire to fill Johnson’s role as tight ends coach, but should have continuity in 2022 for most of the rest of their staff.

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Defensive coordinator Aaron Glenn will return next season after the New Orleans Saints promoted Dennis Allen to head coach on Monday, and every other position coach remains under contract for next season.

Glenn had interviewed for head coaching jobs with the Saints and Denver Broncos this offseason, though both positions have been filled.

NFL Network reported Monday that the Minnesota Vikings have asked permission to interview secondary coach Aubrey Pleasant for their defensive coordinator job. Pleasant worked with Los Angeles Rams offensive coordinator Kevin O’Connell, who is expected to be named Vikings head coach after the Super Bowl.

Contact Dave Birkett at dbirkett@freepress.com. Follow him on Twitter @davebirkett.

This article originally appeared on Detroit Free Press: Detroit Lions hire Ben Johnson as new offensive coordinator