There’s no bitterness, no resentment as the clock ticks down on his last days with the Detroit Lions. But as he heads towards free agency next week, where he’s sure to sign a colossal contract with a new team, Graham Glasgow does have mixed emotions.

“I’m bummed that I’m not able to stay cause I love Michigan and I love the Detroit area, Ann Arbor,” Glasgow told the Free Press in a phone interview Monday night. “I’ve been here for almost about a decade now and it’s awesome and I really, really like the guys in the locker room and I think we have a good team and a good group of guys. So in that regards, it sucks. But you don’t play football forever, so I think that being able to go somewhere else and make some money is an exciting thing.”

Glasgow, who spent five seasons at Michigan football and played the last four years with the Lions, will be one of the most coveted offensive linemen in a free agent market that should be flush with cash regardless of whether players approve a new collective bargaining agreement this weekend.

He’s still in the prime of his career, a few months shy of his 28th birthday. He’s dependable, having missed just one game the last four seasons because of injury. He’s versatile, capable of playing every interior line position. And he’s been one of the Lions’ best blockers for the duration of his career.

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That’s why the decision to let Glasgow go is a head-scratcher for a team that says it values all those traits and has invested heavily – with mixed results – in its offensive line over the years.

Glasgow, who has started 58 of a possible 64 games in Detroit, said he expects to sign with another team next week – “I mean, yeah. That’s the way it seems,” he said – after lukewarm talks with the Lions dating back to last summer.

The free agent negotiating period opens at noon Monday, and players are eligible to sign with other teams beginning 4 p.m. next Wednesday.

“I’m just here waiting for Monday to come along and that’s when the legal tampering (period) or whatever it is (begins),” Glasgow said. “So just kind of waiting to see what goes on there and we’ll go from there. Haven’t really heard too much from the Lions, so we’re just approaching it like that.”

A third-round pick in 2016 who has played most of his career for just above the league minimum, Glasgow is in line for a contract that should top $10 million annually.

He’s widely considered the second-best interior lineman on the market behind New England Patriots left guard Joe Thuney – Washington guard Brandon Scherff is expected to get the franchise tag – and his versatility adds to his appeal.

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“That’s something that worked out well for me,” Glasgow said. “I can play both (guard and center), I can play both well, so that’s just something that works out to where, it’s not like I want to play one more than the other. I think that it just comes down to seeing who wants me to play where for what, at what position, and I think that that’s just everything is going to come into account that way.”

Glasgow, who split his time between center and left guard his first two NFL seasons, took over as the Lions’ full-time center in 2018 before moving to right guard last year.

He ranked among the top 10 guards in the NFL last season, according to Pro Football Focus, and the Lions’ decision to let him walk is largely financially motivated.

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The Lions have $19.35 million tied up in tackles Taylor Decker and Rick Wagner this season and hope to sign Decker to an extension before he hits free agency next year. They’re already planning for a future contract for center Frank Ragnow, their first-round pick in 2018, and are wary of handing out too many big deals to their offensive line.

“It just kind of comes down to, it’s a business,” Glasgow said. “Like, it’s a business for them and I understand that you can’t pay everybody, so that’s fine.”

Still, the decision to not pay Glasgow is confusing.

Glasgow has been the Lions’ most reliable offensive lineman the last few seasons, even if he hasn’t made a Pro Bowl. The Lions have the cap space (an estimated $47 million, according to Over The Cap) to afford him and fill some of the other holes on their roster. And letting him walk leaves the Lions with question marks at both guard spots, with no in-house replacement ready to take over at right guard and left guard Joe Dahl coming off a concerning season-ending back injury.

Glasgow, who got married last month, said he hasn’t received an explanation for why the Lions are moving on, and he isn't seeking one.

“They’re pretty tight-lipped about a lot of stuff in there so I imagine that you’re not going to get an explanation to that and I probably really won’t either, so that’s something that I’ve already accepted,” he said.

As for free agency, where he's completely open to team, coach and scheme, Glasgow said the build-up is reminiscent of his recent wedding, where he and his bride put months of planning into one big day and all a sudden his new reality was there.

“Me and my agent joke around, I’ve been doing all the work for four years, it’s about time he has to do something,” Glasgow said. “But we’re just, he’s going to go and talk with some teams and then from there we’ll see what happens later in the week.”

Contact Dave Birkett at dbirkett@freepress.com. Follow him on Twitter @davebirkett. Read more on the Detroit Lions and sign up for our Lions newsletter.