Vikings coach Mike Zimmer is operating under the assumption that he will have the services of starting wide receivers Mike Wallace and Charles Johnson on Sunday, something that seemed far from a sure thing a few days ago.

Wallace, who banged up a knee in a Week 4 loss to the Denver Broncos, returned to practice Thursday and was a limited participant. So was Johnson, who has now practiced two straight days after missing the Broncos game because of a rib injury.

Jarius Wright, another receiver, was a full participant for a second straight day.

If all three are available to play the Kansas City Chiefs, the Vikings will have to decide whether they want to dress six receivers, something they have yet to do this season. If not, then who sits out?

“It’s not really in our best interest to tell Kansas City what we’re doing, and how we’re doing it and why we’re doing it,” offensive coordinator Norv Turner said.

Johnson, Wallace and Wright are the top three receivers on the depth chart, so if they are deemed healthy enough to play, one can assume they will.

Rookie Stefon Diggs and special-teams standout Adam Thielen both made cases for more offensive snaps by catching six passes apiece against the Broncos.

Cordarrelle Patterson, however, did not make the most of his opportunity, with just one catch for 9 yards. And while he is the team’s top kickoff returner, special teams coordinator Mike Priefer said he would trust cornerback Marcus Sherels or Diggs to do that job if circumstances required it.

Patterson has never been a healthy scratch in his 2 ½ years in the league.

Zimmer, who has the final say when it comes to choosing which players are active on gameday, doesn’t think this numbers game is a bad problem to have.

“The thing I keep telling them is, ‘You never know when it’s going to be your day,’ ” he said. “You know, it’s always a good thing to have depth.”

Ellison injures knee

Rhett Ellison, the team’s best blocking tight end, was added to the injury report with a knee injury. He was limited in Thursday’s practice.

Safety Andrew Sendejo (knee) and cornerback Jabari Price (shoulder) were also limited. Defensive end Justin Trattou (ankle) was the only Vikings player to sit out the session.

A tough cover

The Chiefs have a pretty good weapon in Travis Kelce, who ranks third among tight ends with 24 receptions and 328 receiving yards. Only wide receiver Jeremy Maclin has been targeted more than the 6-foot-5, 260-pound Kelce.

“He’s a tough cover,” defensive coordinator George Edwards said. “We’ve got to do a good job of containing him.”

Through four games, the Vikings have allowed opposing tight ends to catch 18 passes for 179 yards and two touchdowns.

But Kelce, who was timed at 4.51 in the 40-yard dash before he was drafted in 2013, figures to present a tougher test for Zimmer’s defense, which typically uses a committee to cover tight ends.

No complaints here

So far, the Vikings, who rank 12th in the NFL in pass defense, have been able to get by just fine without the regular services of first-round draft pick Trae Waynes. And Priefer wouldn’t mind if that were to continue.

Priefer has been using Waynes as one of his gunners on the punt coverage team and is having him run downfield to cover kickoffs. These are unfamiliar roles for the former Michigan State cornerback, but Priefer sees a willingness to improve and corresponding results.

“It’s always nice to have a first-round-draft-pick-type athlete on special teams, and we’re going to use him for as long as we can until he becomes a starter here at corner,” Priefer said.