Overreaction Monday: Root cause of Chiefs' inevitable downfall is already clear

The Kansas City Chiefs improved to an NFL-best 10-1 record in Week 12, but they certainly haven’t appeared to be the best team in the league.

Of course, we’ve seen this movie before: the dynasty struggles, the media declares its demise, and then the team kicks into high gear after Thanksgiving. The New England Patriots followed that storyline for 19 seasons, and Kansas City has kept the tradition alive ever since. 

Still, there are valid concerns with the defending Super Bowl champions. When the season began, many suspected that the most glaring weaknesses would be on the offensive side of the ball. After all, it was the team’s defense that carried it to a championship in Super Bowl LVIII.

Instead, the defense has wavered just as the offense appears to have found its rhythm. Kansas City avoided a major upset with kicker Spencer Shrader’s 31-yard field goal on the final play of a 30-27 victory over the Carolina Panthers in Week 12. Still, the game should never have been that close.

The Chiefs secondary is becoming a significant concern

Kansas City’s passing defense appears to have gone from riches to rags as the depth behind top cornerback Trent McDuffie has become quite shallow. The Chiefs traded cornerback L’Jarius Sneed to the Tennessee Titans during the offseason, and former fourth-round pick Jaylen Watson was placed on injured reserve after undergoing surgery for a broken tibia and fibula.

Since Watson’s injury, the Chiefs have ranked as the fifth-worst defensive unit in EPA allowed per dropback (0.234) and EPA allowed per play (0.107), according to rbsdm. Through the first seven weeks of the season, they ranked ninth-best in EPA allowed per dropback (-0.024) and eighth-best in EPA allowed per play (-0.066). 

The Chiefs were outbid on a potential trade for four-time Pro Bowl cornerback Marshon Lattimore before the trade deadline, leaving them with few options to bolster their struggling secondary. 

On Sunday, McDuffie and cornerback Chamarri Conner took turns accruing pass interference penalties in the end zone, which allowed the Panthers to score a touchdown and two-point conversion to tie the game with under two minutes remaining.

Kansas City took a 20-9 lead in the first half after holding the Panthers to three field goals in three red zone trips. That was enough to hold off a second-half rally from Panthers quarterback Bryce Young, but it will be hard to replicate that performance against teams with better offenses than Carolina. The Panthers entered the game ranked 30th in points scored and last in total yards. 

Great quarterbacks can evaluate a game in real time and manage it accordingly. Like Tom Brady before him, Chiefs quarterback Patrick Mahomes has managed risk and done what has been required. Lately, he’s had to do more to remain competitive. 

The Chiefs have allowed at least 24 points in three of their four games in November. That’s a concerning decline after a 2023 campaign in which they allowed just 17.2 points per game, the second-fewest in the NFL.

Mahomes has thrown for three passing touchdowns and no interceptions in three of those four games, but Kansas City has still dealt with narrow victories and a loss in that span. The Chiefs have an average margin of victory of just 3.6 points this month. 

Chiefs defensive coordinator Steve Spagnuolo will have to conjure up some of his signature magic to get this unit back on track before the postseason.