Matt Eberflus is the new coach of the Chicago Bears, tasked with turning around a franchise mired in mediocrity for much of the past decade.

The Bears announced Eberflus’ hiring on Thursday night. He spent the past four years as Indianapolis’ defensive coordinator.

The 51-year-old Eberflus called his new job a “once-in-a-lifetime opportunity.”

With Eberflus in charge, Indianapolis’ defense showed marked improvement after ranking among the league’s worst. The Colts ranked eighth on defense in 2020, though they slipped to 16th this season.

Indianapolis missed the playoffs at 9-8, closing with two straight losses when a win in either game would have clinched a postseason berth.

The hire is the first big move for new Bears general manager Ryan Poles, who took over on Tuesday. Poles and Eberflus are first-timers in their respective positions in the NFL.

The first big question for Eberflus is his offensive coordinator, since a big part of the job for the new coach and GM will be solidifying the quarterback position that has haunted the founding NFL franchise for decades.

That likely means figuring out a way to get the most out of Justin Fields and surrounding him with the cast to help him develop. The former Ohio State star had a shaky rookie season, though he also showed potential.

Eberflus, a former linebacker at the University of Toledo who began his coaching career at his alma mater and hometown school, also interviewed for head coaching jobs last year after his third season with Indy, where he developed a reputation for demanding relentless effort out of his players.

Chicago ranked 24th in yards per game and 27th in scoring last season. And the Bears never finished higher than 21st on offense under Nagy.

Fields showed the arm, speed and poise that convinced Pace to trade up nine spots with the New York Giants to draft him with the No. 11 overall pick. But he also has plenty of room to grow.

Fields took over as the starter after Andy Dalton was injured in Week 2. He threw more interceptions (10) than touchdown passes (seven) to go with an unimpressive 73.2 passer rating. Fields also missed time because of rib and ankle injuries. And the Bears were 2-8 in the games he started.

The Bears fired general manager Ryan Pace and coach Matt Nagy after a 6-11 season, hoping new leadership will lift a struggling franchise. They brought in Hall of Fame executive Bill Polian to lead a five-person search team that also included chairman George McCaskey and president Ted Phillips.