KANSAS CITY, Mo. -- The Kansas City Chiefs selected seven defensive players in this year's NFL draft, including two in the first round for the first time in franchise history. Many will get an immediate chance to impact the team's fortunes, something that's not lost on the group.

"This class definitely came in trying to prove a point," said cornerback Trent McDuffie, the Chiefs' top draft pick at No. 21 overall. "Everybody is very confident. ... They're just willing to do the dirty work, which is something I know I can do. I love being a part of that."

The race is on for the Chiefs to get McDuffie and his many fellow first-year defensive players ready for the regular-season opener on Sept. 11 at the Arizona Cardinals. The Chiefs are halfway through their four weeks of offseason practice before they gather again in late July for the start of training camp.

The Chiefs lost several veteran defensive players during the offseason, including safety Tyrann Mathieu, cornerback Charvarius Ward, linebacker Anthony Hitchens and defensive end Melvin Ingram.

They've turned to rookies in many cases to replace them. McDuffie, defensive end George Karlaftis, cornerback Joshua Williams, safety Bryan Cook and linebacker Leo Chenal are among the first-year defensive players getting a good run so far in offseason practice.

They have much to prove to defensive coordinator Steve Spagnuolo, who has made rookies repeatedly prove their worth before putting them in the lineup since joining the Chiefs in 2019. He may have to compromise that notion this year with the Chiefs counting on so many of their defensive rookies.

"We're going to have to live with some growing pains," Spagnuolo said. "I believe that. Hopefully we can overcome that. But I think that's the only way we're going to get it to where we need it to go because some guys are going to need to step up and play. We need to find out about the guys that we have now. There are a lot of unknowns from a coaching standpoint: What can this guy do? Can he do the same thing somebody did last year? That may or may not be the case. It's going to take some time.

"I'm throwing a lot at them right now. The volume is huge right now for a reason. Find out who can handle it and who can't. ... There will be mistakes out there that normally we wouldn't make."

Many of the Chiefs' significant free-agent additions this year were on offense. Their only major veteran addition on defense was a safety, Justin Reid. So it's not a coincidence they invested so heavily on defense in the draft.

"You have to have balance on both sides of the football and we wanted to upgrade the youth, the talent and the depth on the defensive side," general manager Brett Veach said. "We also did some stuff offensively in free agency. We brought in [wide receivers] JuJu [Smith-Schuster] and we brought in MVS [Marquez Valdes-Scantling] and we brought in [running back Ronald Jones].

"Certainly, the draft was geared more toward defense and I think it's a combination of us wanting to certainly get better and get deeper and younger. But had we not been able to sign the Smith-Schusters and the MVSes and the RoJos, it maybe deviates a little.”

Spagnuolo, always a teacher, can often be seen at practice working one-on-one off to the side with a player. And he's as much of a teacher as ever now. At a practice last week he pulled aside Williams, a fourth-round draft pick, to display an improvement on a technique Williams had used in coverage on the previous play.

"He does a great job of explaining what he needs you to do," said Cook, a second-round draft pick. "It's not rocket science. A lot of teammates and coaches help out the transition. It's not as bad as it may seem. You come in and it's like, 'Oh my gosh, it's a lot of stuff.' But it's not that bad. You just have to figure it out.

"I think we're all in the same boat. We're back to [being] freshman again, trying to figure it out. We all understand that right now it's grind time. It's time to establish yourself and get respect from your teammates and coaches as well as figure out how you can best ready yourself coming in your first year."