The Kansas City Chiefs played just one game after defeating the Baltimore Ravens in the AFC Championship last season: Super Bowl LVIII against the San Francisco 49ers.

But when the two teams meet Thursday night for the NFL season opener at GEHA Field at Arrowhead Stadium, a lot of things will be different — starting with the absence of running back Clyde Edwards-Helaire behind starter Isiah Pacheco. Behind him will be undrafted rookie Carson Steele — and behind it The new signing is veteran Samaje Perine, who only joined the team last week.

“It’s one of those next-man-up mentalities that we all talk about — but it’s real,” Kansas City offensive coordinator Matt Nagy noted when he spoke to reporters Monday. “I think the guys have done a great job in training camp. Pacheco has been phenomenal in understanding his role. And then (with) these other guys — as we get going — (it’s) going to be important for all of us to make sure that, whether it’s running the ball, protection, in the passing game, that everybody knows, no matter who it is, that they feel really good about their assignments.”

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Nagy doesn’t seem too concerned about whether Steele understands what is expected of him.

“His assignments in OTAs were pretty sharp,” Nagy recalled. “He knew what he was doing; he knew where he was going. (But) you never know how (someone) is going to do it until (they) put the pads on. He took it to training camp, put the pads on and made some nice plays. A splash play here and there certainly helps, but it’s got to be consistent over periods of plays and (through) series of drives. I thought he did that.

“There’s still things that we know internally that he can get better at — (and) he knows it. Now he’s (taking) it to ‘Thursday Night Football’ against a really good football team, balancing ‘the emotions of understanding.’

“There will be some mistakes, but he’ll do it 100% — 100% of the time.”

Meanwhile, Nagy said the team’s coaches are still trying to figure out what Perine can do.

“How much can (he) handle? What’s too much? What’s not enough? There’s a balance (there). But one thing I’ve definitely learned from the (few) days I’ve been with him is that (he’s) super smart. He’s a real professional; he gets it.”

But those aren’t the only new faces on the Kansas City offense. Second-round rookie Kingsley Suamataia will start at left tackle, with the key role being protecting quarterback Patrick Mahomes.

“I think he’s shown us physically that he can do some good things,” Nagy said of the former BYU tackle. “Again, it’s the mindset of understanding. Coach Reid always talks about, ‘You have training camp, you have preseason, and then you get to the season. And then as you go through the season, you get to the playoffs, and you get to the Super Bowl. Every game gets more physical — and more physically.’ So for him it will be a challenge.”

“But at the same time, you have to be mentally strong in these games. That’s our job as coaches: to make sure we understand that there are young guys playing their first game. Are we giving them enough mental help – to give them the best chance to succeed?”

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That will be very important for another rookie: wide receiver Xavier Worthy.

“Probably the biggest thing is making sure (he) understands that this is going to be an emotional game,” Nagy noted. “(He has to understand) that there are going to be times where a mistake is made on a route assignment — but there are also going to be big plays.”

Nagy believes the former Texas wideout is ready for Thursday’s challenge. But there will be challenges for the coaches against the Ravens, too.

“For every team, this whole first week is about adjustment,” Nagy explained. “That’s it. How do you adjust? How well do you adjust? They have a new defensive coordinator. He’s calling plays for the first time. Whether that’s the same or different, we’ll see.

“But they’re going to have some undiscovered looks; we’re going to see some things that are different. How do we adapt?

“It’s important that our guys can play fast, but we also have a lot of respect for them. And it’s going to be a physical game.”