DETROIT — Jim Leyland’s decision to retire as the manager of perennial playoff contender might seem strange to some people. For someone who recently called himself a weird guy, and to those who saw him on a regular basis, it wasn’t that much of a surprise.

The fire in his gut to win championships hadn’t flickered. But the stress and grind, along with some nasty habits, pushed the mind and body of the 68-year-old baseball lifer into burnout mode.

Comerica Park wasn’t just a workplace for Leyland. During a Detroit Tigers season, it was his primary place of residence.

He’d often rest overnight in the manager’s office, though sleep was a relative term. He would doze off for a little awhile but thoughts of what he could have done better that night and what need to be done the next day never exited his restless mind. He’d get an hour or two of sleep, then wake up in the wee hours and click on the TV or read a scouting report.

Breaking away from the criticism, or praise, by the beat reporters, talk-show hosts and fans was never an option. He cared about what others said about him and his ball club.

He had all the game stories or columns delivered to him daily. He was well aware of the swipes taken at him for his old-school style of managing and disdain for advanced stats.

Bad lifestyle choices followed Leyland wherever he managed. He couldn’t stop smoking and no one ever accused him of being a health-food nut. Media members would sometimes walk into Leyland’s office for the pregame press conference and see him stretched out on the couch, a blanket over his legs, while he took turns smoking a cigarette, eating a bag of potato chips and M&Ms and sipping a soft drink.

Toss in the constant travel and lack of family time and the players issues and egos and Jim Leyland simply didn’t have the energy to make it through another spring training, another 162-game regular season and another postseason run with the weight of enormous expectations on his weary shoulders.

Like his good buddy Tony LaRussa opted to do two seasons earlier, Leyland can now find out what it’s like to have a free summer.

Leyland, who will remain with the Tigers in some capacity, can now watch his son Patrick — a minor leaguer in the Tigers organization — play ball. He can head up to Saratoga in upstate New York to watch and play the ponies on a sunsplashed August afternoon, something he said last season was on his bucket list. He can delve into his treasure trove of stories at speaking engagements and provoke belly laughs without pondering the next day’s lineup in the back of his mind. And he can finally get a good night’s sleep.

He’ll be a difficult act to follow for the candidate that general manager Dave Dombrowski and owner Mike Ilitch chooses to lead the Tigers to capture the ultimate prize that has eluded them since Kirk Gibson blasted a Series-clinching homer at Tiger Stadium in 1984.

The lockers are filled with strong personalities like Prince Fielder, Miguel Cabrera, Torii Hunter and Justin Verlander. Leyland allowed his veterans to police the clubhouse and expected men to act like men. He earned the respect of his players with his knowledge, passion and loyalty. The next man in the office might want to blow the smoke out of the manager’s office but he better not try to blow any smoke past the clubhouse leaders down the hallway.

Dombrowski will consider in-house candidates like Gene Lamont and Lloyd McClendon. He’ll look outside at proven managers like Dusty Baker and Gibson, though it’s unlikely Arizona would allow Gibson to leave. He’ll mull hotter, younger names like Brad Ausmus.

Whoever gets the job will have to deal with the same championship-or-bust mentality that weighed on Leyland. The Tigers have some holes but are in great shape for the short term.

Verlander and American League ERA champion Anibal Sanchez are locked up to long-term deals. Cabrera, Fielder and Victor Martinez will continue to form arguably baseball’s most menacing middle of the order. They also have a slick-fielding young shortstop in Jose Iglesias and youthful, talented arms in Rick Porcello and Drew Smyly, who might move from the bullpen to the rotation next season.

They have decisions to make regarding second base, as Omar Infante heads into free agency, and left field, which was a black hole much of the season. Dombrowski has to straighten out his shaky bullpen, as aging closer Joaquin Benoit also heads into free agency. Benoit’s potential flamethrowing replacement, Bruce Rondon, had some late-season arm issues that may give the organization pause over handing him that all-important role.

Most of all, Dombrowski must figure out whether the organization can afford to sign likely Cy Young winner Max Scherzer to another Verlander-sized contract or cash him in this offseason for a king’s ransom. Dombrowski has never been afraid to pull the trigger on a blockbuster and he could get some much-needed, high-powered bullpen arms and a quality leadoff hitter for Scherzer.

Leyland could still get that World Series ring he wanted so badly to deliver to the organization where he started his long and storied career. He’ll still be a part of the franchise, but now he’ll only have to dedicate a smaller piece of himself. He knew better than anyone else as his final managerial season winded down to its disappointing conclusion, it’s all he has left to give.