ALLEN PARK >> If the future outlook of the Detroit Lions’ offensive line were a stock ticker, it would have both spiked and crashed at several points in the last few months.

Christian Mahogany, a sixth-round pick a year ago, showed early signs of promise when making two spot starts toward the end of last season, including Detroit’s playoff loss to Washington. But the offseason began with Kevin Zeitler, an uber-reliable right guard who spent one season in Detroit, departing for a deal with the Tennessee Titans in free agency.

That was followed by the team investing heavily in the interior of its offensive line by spending a second- and fifth-round pick on guards while securing much of the depth that carried it through last season. Then came another massive, short-term drop, as center Frank Ragnow announced his sudden retirement on June 2.

But one of the forgotten assets of Detroit’s future quietly has been improving his value behind the scenes in Allen Park.

Giovanni Manu, a Tongan offensive tackle who played college football in British Columbia and was drafted with a fourth-round pick in 2024, didn’t appear in a game last season. But the staff has been pleased with his development over the last 12 months, and we could see an entirely different player when the pads come on in July.

Lions general manager Brad Holmes said in January that Manu’s development is “literally night and day.” However, offensive line coach Hank Fraley warned what comes next will not come easily.

“The one thing, he does have a physical presence about him, and he can exert his physicality on the field. That’s what I think you got to see later in the year,” Fraley said. “Now, it’s can he take that next step? It’s a huge step. It’s no longer, ‘Hey, we’re trying to get all your base and balance right.”

Upon being drafted, he was immediately tabbed as a project. Attending high school and college in British Columbia wasn’t exactly conducive to his development, and much of his first pro season was about shedding bad habits and building good ones.

“There was a lot we changed with him. I told him when we drafted him there was going to be a lot that I was going to change how he did things,” Fraley said. “You’re coached four or five years one way, you’re coming to a new coach that might want you to do this, tweak that foot there, turn your toe out, place your hands here, all that.

“All these little things, he’s heard me a whole year saying it, and it’s, ‘Can I take this, and now, without thinking of all these little things that come into play, can I keep playing fast?’ I think that’s what we’re going to see now.”

Though Lions coach Dan Campbell suggested in March the Lions could try Manu at guard, he was taking reps at left tackle during last week’s OTAs. Perhaps that could change with Ragnow’s departure, as the Lions are now on the hook to find three high-level starters for the next season and beyond.

Manu doesn’t currently have a path to a starting role at tackle, so it’s expected he will keep developing in the background for at least the next few years. Two-time All-Pro right tackle Penei Sewell is still just 24 and considered one of the best tackles in the league, and left tackle Taylor Decker signed a three-year extension that kicks in this year.

But long-term, if a player with Manu’s size (6-foot-7, 350 pounds) and athleticism can scrape the ceiling that Detroit thinks he has, he could eventually send the ticker tracking Detroit’s future skyrocketing upward.