Revamped defense plus Kenneth Walker III: How the Chiefs re-established themselves as a Super Bowl contender

Kenneth Walker III’s league-leading ground game and Steve Spagnuolo’s revamped, pressure-heavy defense are taking the burden off Patrick Mahomes

The Kansas City Chiefs had won the AFC West nine consecutive years before missing the playoffs last season. For the majority of the decade, they were a free space on the NFL's postseason Bingo card. But in 2025, for the first time in Patrick Mahomes' career, the media stopped giving the franchise the benefit of the doubt regarding being one of the last teams standing. After four weeks of this year's regular season, Kansas City looks like the formidable Kansas City teams of old. While legacy names such as tight end Travis Kelce and defensive tackle Chris Jones are still around, several newcomers, including a strong rookie defensive class, have inspired newfound confidence — and taken the burden off Mahomes to get the Chiefs back to Super Bowl contention.

Prized free agent running back acquisition Kenneth Walker III leads the NFL in rushing (537) yards as the league trends more run heavy, but it was a defensive overhaul that has been the biggest change for the Chiefs. Roughly 35% of defensive snaps this season have been played by those who were not on the roster a year ago. In terms of defensive EPA per play, through four weeks, the Chiefs have their best mark (0.04) since winning the Super Bowl in 2024. The pass rush is a big reason for