KANSAS CITY, Mo. -- The Kansas City Chiefs expected things to be bumpy at times in their season opener without injured tight end Travis Kelce in their lineup. They didn't necessarily expect their offense to struggle as much as it did in their 21-20 loss to the Detroit Lions.

"It's going to have an impact on the game," quarterback Patrick Mahomes said of Kelce's absence. "But other guys have to step up and they're going to have to step up in moments. Sure, there'll be times [after Kelce returns] that he gets doubled and so we're just going to have to rely on these other guys that are young and talented to step up and make plays, and I believe that they will."

That didn't happen against the Lions. The Chiefs dropped numerous passes, none more damaging than the seemingly easy catch that Kadarius Toney deflected to Lions safety Brian Branch, whose interception and return for a touchdown in the third quarter was the game's defining play.

The Chiefs were hopeful Toney could be their No. 1 wide receiver. But he missed all of training camp after having surgery for a torn meniscus and only recently returned to practice.

He dropped two other passes and wound up with one catch for one yard.

"I have trust in [Toney]," Mahomes said. "He missed a lot of training camp, and obviously he wanted to play and fought [during] rehab hard so he could play and stuff's not always going to go your way.

"Obviously he would've wanted to catch a few of those in the game, but I've trusted he's going to be that guy that I go to in those crucial moments, and he's going to make the catch and win us some games like he did last year. So we're going to continue to work him in, get him more and more reps, and I'm sure that those drops will kind of disappear."

Mahomes was 10-of-22 (46%) throwing to wide receivers, his worst completion percentage to wideouts in 35 career games in which he has attempted at least 20 passes. The Chiefs' leading receiver was running back Isiah Pacheco, who had four catches.

The Chiefs were hopeful Kelce, who hyperextended his knee in practice two days before the game, could have played. But coach Andy Reid indicated the decision to sit Kelce wasn't a difficult one.

"It just wasn't feeling right, so I wasn't going to put him out there with that," Reid said. "And he was honest with me and we talked, so just not enough time there."

A Week 2 game against the Jaguars in Jacksonville is next for the Chiefs. They will work to get Kelce ready for that game. Judging from the way they played against the Lions, they're going to need him.

"I'm not going to put anything past Trav," Mahomes said. "He was trying to play today. He just literally couldn't. I don't even know if it was his decision. It was kind of the guys above him knowing it's going to be a long season.

"He's going to try. He'll do whatever he can to be out there, and hopefully he can clear all those doctors' tests and then get out there on the football field."