Allen Park — Entering a primetime matchup against arguably the greatest quarterback of his generation, the Detroit Lions could be without four of their five starters in the secondary.

Lions coach Dan Campbell said safeties Brian Branch (ankle) and Kerby Joseph (knee) will not practice and will be gametime decisions for Sunday’s game against the Kansas City Chiefs and quarterback Patrick Mahomes. Both players are officially listed as questionable.

Joseph has been dealing with a lingering knee issue since training camp and suffered a different knee injury in Week 4 that briefly forced him out of a win against the Cleveland Browns. Branch, meanwhile, exited Sunday’s win against Cincinnati with an injury but returned to finish the game before being limited with an ankle injury on Wednesday and Thursday.

On Branch, whose injury is new, Campbell said he doesn’t feel like it’s a long-term concern despite the immediate uncertainty with his availability.

“It’ll come down to how he’s going to feel for this game. But I don’t feel like this is some long-term thing, by any means,” Campbell said. “I feel like we’re going to get him to (play in) the game, I really do. But we’ll see. I can’t sit here and guarantee it, either.”

The Lions were already going to be without starting cornerbacks D.J. Reed and Terrion Arnold, plus reserve cornerback Khalil Dorsey, who went on injured reserve with a wrist injury this week. Compounding the matter is that defensive back Avonte Maddox is also now dealing with a hamstring injury and will be another gametime decision. Maddox is also listed as questionable.

Amik Robertson and Rock Ya-Sin are expected to fill in as the starting outside cornerbacks. If any combination of Branch, Joseph and Maddox also can’t go, the Lions will rely on a mix of safeties Thomas Harper and Loren Strickland, who are currently on the active roster, as well as practice-squad defensive backs like Tre Flowers, Arthur Maulet, Nick Whiteside and Erick Hallett II.

Like most units on the football field, the secondary heavily relies on rock-solid communication to execute down-in, down-out. Campbell said the team is doing “the best you can with” getting all of the players familiar with the scheme and ready to carry out their responsibilities.

“The good news is all of those guys have gotten reps. Every one of those guys have gotten defensive reps — the guys on the practice squad, I’m talking about all of them,” Campbell said. “… Now, is it the same amount of reps everybody else (is getting)? No, but they’re in there, they know the game plan, they’re prepared to play any and all (things). Listen, that’s the hand you’re dealt.

“We better be ready.”

More injury updates

The Lions ruled out four players: Cornerback Terrion Arnold (shoulder), linebacker Zach Cunningham (hamstring), defensive tackle Alim McNeill (knee) and running back Sione Vaki (groin).

▶ OT Taylor Decker (questionable): Decker missed last week’s game against Cincinnati with a lingering shoulder issue and has not practiced for much of this season. Detroit is trying to aid his recovery by giving him some time to rest, but it’s unclear how long that plan will hold.

“He’s getting better. I think we’ll know a lot more after (Friday). We get through this practice, rehab, all that,” Campbell said.

▶ OT Giovanni Manu (questionable): Manu, who started in place of Decker last Sunday, was limited in Thursday’s practice with a knee injury and was not spotted at practice on Friday. His status will likely be a gametime decision as well.

▶ DT Alim McNeill (out): McNeill was hoping to return to action for the first time since last December, when he suffered a season-ending knee injury, but he was ruled out on Friday’s injury report.

“I’ve been working out, doing this, this and that, doing everything but football,” McNeill said Friday. “Now that I’m back in football, it feels good. Everything feels like it’s back in motion, back in the fold, so yeah, I was excited to get out there at practice and put force into somebody else. I’m ready, though, 100%.”

▶ WR Kalif Raymond (questionable): Raymond is questionable with a neck injury that forced him out of last week’s game against Cincinnati.

Chiefs injury updates

The Chiefs are as healthy as a team can be entering Sunday’s contest. The only uncertainty was wide receiver Xavier Worthy, who picked up an ankle injury in Monday’s game against the Jaguars and did not practice Thursday.

Worthy practiced fully on Friday and is officially off the injury report with no game designation.