Just when it looked like the Detroit Lions might be able to start digging out of their injury problems in the secondary, Dan Campbell delivered another Thomas Harper injury update nobody wanted to hear.

Safety Thomas Harper was placed on injured reserve over the weekend because of an ankle injury, guaranteeing that he will miss at least four games. But when Campbell was asked Monday whether Harper could potentially miss the remainder of the 2026 season, the Lions head coach couldn’t offer much reassurance.

“I don’t know with the Harper deal,” Campbell said. “We’ll see. He’s IR right now, so we’ll see on that. I just know he won’t be here for four weeks or whatever for sure.”

That is considerably different from simply waiting out a four-game stint on injured reserve.

Lions’ Safety Room Continues to Take Hits

Harper’s injury would be problematic under any circumstances. Considering what has already happened to Detroit’s secondary, the timing makes it much worse.

The Lions entered the season without Brian Branch and Kerby Joseph, who both began the year on the PUP list. Campbell recently acknowledged that neither Branch nor Joseph was ready to return to practice, although Branch appears to have a chance to return before Joseph.

Then came another blow.

Avonte Maddox suffered a foot injury against the Buffalo Bills that required surgery, ending his 2026 season.

Now Harper is gone, and there is no guarantee he will be back.

Harper appeared in 12 games with nine starts for Detroit last season, finishing with 37 tackles, five passes defended, an interception and a forced fumble. He had appeared in Detroit’s first two games this season before the ankle injury landed him on IR.

Detroit Is Running Out of Safeties

The good news is that the Lions managed to survive Sunday.

With Harper unavailable, Christian Izien stepped into a larger role alongside veteran Chuck Clark as Detroit defeated the New York Jets 31-24. Clark ultimately delivered the biggest defensive play of the afternoon with his game-sealing strip-sack.

But surviving one game is different from navigating an extended stretch without several of your best defensive backs.

What the Thomas Harper Injury Update Means for Branch and Joseph

Harper joins Maddox, Branch and Joseph among Detroit’s unavailable safeties. Branch and Joseph are technically eligible to begin working toward a return, but Campbell has made it clear that Detroit will not rush either player back simply because the position has been decimated.

Branch has a chance to begin ramping up his football work in the coming weeks, while Joseph’s timeline remains considerably less certain. Campbell recently admitted there wasn’t much he could say that would make anyone feel better about Joseph’s situation, while indicating Branch has a better chance of returning first.

That leaves Clark, Izien and Detroit’s collection of depth defensive backs carrying a significant burden in the meantime.

And Harper’s latest prognosis removes one potential reinforcement from the equation.

Putting a player on injured reserve doesn’t necessarily mean his season is finished. In Harper’s case, though, Campbell isn’t willing to say he’ll be back.

For a Lions secondary already operating without Branch, Joseph and Maddox, that’s one more uncertainty Detroit really didn’t need.