DETROIT — If you want to know what it takes for a cornerback to see the field for the Detroit Lions, watch the play that took their best one off of it.

The Lions were playing the Browns. Joe Flacco lofted a ball down the left sideline, intended for Jerry Jeudy, with Lions CB D.J. Reed in coverage. Before it even landed, Reed was in noticeable pain, reaching for his hamstring.

He couldn’t make a play on the ball, but still managed to stick an arm out from the ground — doing just enough to disrupt the play for an incompletion. A play that encapsulates his football character and what the Lions look for from this position.

“It’s the way he’s wired,” Dan Campbell said. “That’s the type of guy he is.”

“That was just me trying to make a play,” Reed said Wednesday. “I didn’t even know I did that.”

What Reed did know, right then and there, was that he had suffered an injury that would keep him out of commission for an extended period. Reed told reporters Wednesday he thought he tore his hamstring “off the bone.” A cart came out for him as his teammates took a knee around him. He would not return in that game and did not practice Wednesday. He was placed on injured reserve several hours later. He was diagnosed with a Grade 2/3 hamstring injury, but his prognosis won’t require surgery — just rehab.

An unfortunate injury for one of the best players on this defense. But it comes with a silver lining.

“He’s going to be down for a while,” Campbell said earlier this week. “But the good news is this is not a season-ender. We will get him back, it looks like, so that’s the good news. He’s a stud.”

Reed missing the season would’ve been a brutal blow to a defense still scarred from the events of last year’s injury-riddled 15-2 season. As things stand, he’ll miss the next four games vs. the Bengals, Chiefs, Buccaneers and Vikings after the bye. The earliest he’ll be able to return is Week 10 on the road against the Commanders. Again, that’s the early end of the timeline.

Replacing him, in the meantime, will be tough. Reed was brought here to play and play a lot. The Lions signed him to a three-year, $48 million contract this offseason — the largest contract given to an external free agent of the Campbell era. It speaks volumes about the level of trust they have in him, despite him not being a homegrown talent.

Through four games this season, Reed has been one of the best cornerbacks in football. He’s PFF’s 21st-graded cornerback overall, and its seventh-best in run defense. He’s allowed a passer rating when targeted of 61.3 — good for 22nd among qualified corners (minimum 40 coverage snaps). He’s played the 10th-most man coverage snaps of any corner in the league this season. And in recent games, Reed has trailed the top receiver of Detroit’s opponents, with the Lions comfortable leaving him on an island if necessary. He’s been a consistently good player in this league, and that hasn’t changed since he arrived in Detroit.

His absence, however, could change how Detroit operates.

“You can tell why he’s been in the league and successful so long,” Lions DBs coach Deshea Townsend said of Reed. “That’s just the way he carries himself. He comes to work every day, he’s the same, and he wants that challenge of playing man. That’s who he is. And in this building, that’s what we’re going to do. We’re gonna line up and play man, we’re gonna stop the run and we’re going to try to make you win on the outside. He is that to a T.”

“When you’re able to play sticky on the back end, the coverage and rush goes hand-in-hand,” Campbell said, when asked about the value of corners who can hold their own. “The stickier you play, you buy yourself a tick to be able to get to the quarterback. He may have to hold it, he’s got to make a perfect throw, lot of times what happens is that’s a sack or it’s a sack-fumble, or it’s a tipped ball or it’s an ill-advised throw that turns into a takeaway. And now all of a sudden, you start getting takeaways, now the next guy believes he’s going to get a takeaway. … There’s this pride that begins to build and it’s — you believe that’s the way you’re meant to play the game. There’s an aggressive nature to it and it’s nothing comes easy and that’s a style we want to play with. Nothing comes easy if you play against our defense and that’s what we want.”

We’ve seen the Lions have success with this style of defense under Aaron Glenn, and it’s continued with Kelvin Sheppard. It was a prerequisite of the job that ultimately went to Sheppard — and something Campbell said he was targeting during the search for a new DC. That commitment was further emphasized by the addition of Reed, who replaced another sticky corner in Carlton Davis III.

The role of the cornerback position in this defense is valuable. Not everyone can play it the way they ask their corners to, and the team is careful about who it brings in for that very reason. The position is inherently thankless, but even more so in this scheme. Having corners who can hold their own in coverage allows the pass rush more time to get after the quarterback and allows Detroit’s safeties to roam the field without concern for the outside. It’s how Brian Branch gets to live in the box and why Kerby Joseph can play so much centerfield, with the Lions tied for third in the NFL in Cover 1 rate, per TruMedia. You have to be comfortable getting beat and moving on quickly when it happens.

The idea was that Reed would pair with 2024 first-round pick Terrion Arnold and form a duo that would prove difficult to throw against. Without Reed, and potentially without Arnold (shoulder), that gets a bit trickier. But the Lions prepared for this.

The next man up in place of Reed is Amik Robertson — Detroit’s starting nickel and a player the Lions trust to uphold their standards at cornerback. His size (5-foot-9) might fool you, but Robertson played more outside cornerback than nickel with the Las Vegas Raiders, prior to signing with the Lions ahead of the 2024 season. We saw him excel there when filling in for Davis as an outside corner last season, with a memorable matchup vs. Justin Jefferson in a Week 18 contest that helped the Lions secure the No. 1 seed in the NFC and a second-consecutive division title.

The Lions don’t take him for granted.

“He worked at being a better nickel,” Townsend said. “He was a corner at LaTech and at the Raiders, and he played nickel sparingly. But he had to work to be a nickel. I think that was the one thing that impresses you the most, is the time that he took to make himself a really good nickel. Because he’s always been a corner on the outside, but to be able to do both sometimes goes overlooked.”

Arnold left Sunday’s game with a shoulder injury, and his status for Week 5 remains unknown. However, he was able to practice Wednesday as a limited participant. That’s a good sign, but if he’s not 100 percent, perhaps the Lions take it easy with their young cornerback so he’s closer to full strength against the Chiefs in Week 6.

If he doesn’t play, expect veteran Rock Ya-Sin to get the nod. Another 2025 free-agent pickup, Ya-Sin is a physical cornerback who fits the team’s mentality. He’s played a lot of NFL snaps and the Lions feel good about the experience he provides.

The Lions already own the second-highest 4-3 rate in the league at 61.3 percent. That’s more than double their 2023 4-3 rate of 28 percent, which led the NFL. It’s unusual to see a team utilize three linebackers at the same time in the modern game, but it works for this group, knowing the talent they have between Jack Campbell, Alex Anzalone and Derrick Barnes. The Lions have only played nickel defense 31.7 percent of the time, per TruMedia (30th), so it’s possible they lean on their base defense with Robertson shifting outside. But when they want to play nickel, local product Avonte Maddox could fill the void if Sheppard doesn’t want to move Robertson around. It’s worth monitoring as the Lions prepare for life without Reed.

Speaking of Reed, he was in good spirits in the locker room Wednesday. He’s optimistic he’ll be able to return to his level of play, after avoiding a season-ending scare.

“I thought it was a wrap,” Reed said, “but that’s not the case, thank God.”

In the meantime, the Lions will certainly miss him.