The Kansas City Chiefs added two younger players to their practice squad on December 30, and the news came after a massive roster shakeup ahead of Week 18.

Before the Christmas Day game against the Denver Broncos, the Chiefs began shifting several veteran players to the injured reserve. After all, the season is over, and there’s no reason to risk any long-term damage if an athlete is banged up.

Not long after, Kansas City replaced those IR designations by promoting reserves up to the 53-man roster from their practice squad. Now, in Week 18, KC has begun the process of refilling its practice squad, although the front office may not finish that task with the season nearly over.

“The Chiefs have signed LB Kam Arnold and DT Marcus Harris to the practice squad,” Chiefs Digest beat reporter Matt Derrick relayed on December 30. He added that these moves “put the Chiefs at 12 spots filled on the 16-player practice squad.”

Along with Derrick’s reporting, this signing news was also confirmed on the NFL transaction log.

More on Chiefs’ Week 18 Signings Kam Arnold & Marcus Harris

Arnold and Harris are both younger players with very little NFL experience, and if you’re wondering why the Chiefs would sign them this late in the season, the answer is most likely that Kansas City is planning to offer them reserve/future contracts.

Once the regular season ends, each team can sign available players and practice squad reserves to reserve/future contracts. This guarantees them a spot on the initial 90-man roster for 2026.

Of course, the Chiefs could still release a reserve/future player later on, but these agreements tie them to the organization at the start of the new league year in March. And Arnold and Harris certainly fit the profile.

Arnold is an undrafted rookie linebacker out of Boston College. The 6-foot-1 defender spent his preseason and training camp with the Washington Commanders, but he did not make the 53-man roster at the cutdown.

At Boston College, Arnold racked up over 250 total tackles, 3 interceptions, and 4.5 sacks over 56 collegiate appearances (41 starts). During the 2025 preseason, he logged 12 total tackles in 3 games.

As for Harris, he’s a former seventh-round pick of the Houston Texans and a second-year pro out of Auburn.

Listed at 6-foot-3 and 295 pounds, Harris was credited with 126 total tackles and 11.0 sacks in college. He started 40 games, appearing in 47 total.

Over 7 preseason outings split between the Texans (in 2024) and the Buffalo Bills (in 2025), Harris recorded 7 total tackles, 2 QB hits, and 1 pass breakup. The pair of defenders will join the Chiefs’ organizational depth.