Everyone acts like the Kansas City Chiefs are invincible. They aren't. Honestly, watching Patrick Mahomes scramble for his life while Travis Kelce tries to find a pocket of space against a triple-team makes you realize how thin the margin for error really is in the NFL. When people ask who did the chiefs lose to lately, they usually aren't just looking for a score. They want to know how the "unbeatable" dynasty finally cracked.
Winning back-to-back Super Bowls creates this weird aura of inevitability. It's fake. In 2025, we saw teams finally stop playing scared. They stopped waiting for Mahomes to make a mistake and started forcing him into them. It wasn't just about one bad bounce or a missed holding call. It was about specific defensive blueprints that finally stuck.
The Buffalo Bills Finally Got Their Revenge
If you follow the AFC, you know the script. Josh Allen plays like a god for three quarters, and then Mahomes does something magical in the final thirteen seconds to ruin Buffalo’s year. Not this time. When we look at who did the chiefs lose to in the 2025 regular season, the Bills stand out because they didn't blink.
The Bills won 31-21 in a game that felt much wider than a ten-point gap. Sean McDermott didn't rely on the blitz. That’s the trap, right? You blitz Mahomes, he finds the hot route, and you're dead. Instead, Buffalo used a "simulated pressure" look that drove the Chiefs' offensive line crazy. They dropped guys into throwing lanes that Mahomes usually owns.
It was frustrating to watch if you’re a Chiefs fan. Isiah Pacheco struggled to find holes because the Bills' interior line played with a level of violence we hadn't seen in their previous matchups. Ed Oliver was a nightmare. He lived in the backfield. By the time the fourth quarter rolled around, the Chiefs looked tired. Not just physically, but mentally drained from trying to outsmart a defense that refused to give up the big play.
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That Weird Sunday Against the Chargers
Divisional games are always a mess. Jim Harbaugh has turned the Los Angeles Chargers into a team that basically wants to get into a fistfight in a phone booth. They don't care about style points. They just want to run the ball and hit you in the mouth.
So, who did the chiefs lose to in the AFC West? The Chargers took one from them in a 17-13 slog. It was ugly. It was rainy. It was exactly the kind of game the Chiefs usually win because they have more talent, but Harbaugh’s squad out-efforted them. Justin Herbert didn't throw for 400 yards. He didn't need to. He just made three key third-down conversions with his legs and let his defense do the rest.
The real story here was the Chiefs' red zone efficiency. Or lack thereof. They went 0-for-3 in the red zone. You can't do that. You just can't. Rashee Rice had a critical fumble near the goal line that changed the entire momentum of the season's middle stretch. It highlighted a recurring issue: the Chiefs' tendency to get "cute" with play-calling when they only need two yards. Sometimes, just run the ball, Andy.
The Bengals Problem Isn't Going Away
Joe Burrow is still the only guy who seems completely unimpressed by the Arrowhead atmosphere. When people ask about the specific teams who did the chiefs lose to, the Bengals are always the most tactical defeat.
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Cincinnati’s Lou Anarumo is a defensive genius. He treats a football field like a chessboard. In their 2025 matchup, he debuted a "bracket" coverage on Travis Kelce that effectively erased him from the game plan. Kelce finished with three catches for 22 yards. That’s it. If you take away the safety valve, Mahomes has to hold the ball longer. When he holds the ball longer, he gets hit.
Ja'Marr Chase also reminded everyone why he's a top-three receiver. He toasted the Chiefs' young secondary for two touchdowns. It wasn't even a matter of bad coverage; it was just better playmaking. The Bengals won 27-24 on a last-second field goal, a hauntingly familiar scoreline for Kansas City.
Why These Losses Feel Different Now
In years past, a Chiefs loss felt like a fluke. A dropped pass here, a weird penalty there. But the teams who did the chiefs lose to in this most recent cycle found real, repeatable flaws.
- Left Tackle Vulnerability: The blindside protection has been shaky. Speed rushers are starting to realize they can beat the Chiefs' tackles around the edge if they time the snap count.
- The "Kelce Clog": Teams are now willing to give up 5-yard runs to Pacheco if it means they can put three bodies around Kelce on every third down.
- Deep Ball Stagnation: The vertical threat isn't what it used to be. Without a consistent burner who commands a double-team deep, safeties are creeping up, making the intermediate middle—Mahomes’ favorite playground—very crowded.
It’s not just about the personnel. It’s about the league catching up. Every defensive coordinator in the NFL spends their entire offseason studying the Chiefs. They have to. You don't beat the king by doing what everyone else does. You beat them by changing the rules of the engagement.
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The Interception Spike
One thing we have to talk about is the turnovers. Mahomes is the best to ever do it, but he’s human. In the games against the teams mentioned above, his interception rate spiked. Why? Because he was trying to force "Mahomes Magic" when the play wasn't there.
When you're down by ten in the fourth quarter against a team like the Bills, you feel the need to make a play. But the Bills knew that. They baited him into throws across the middle that were disguised as open windows but were actually traps. It’s a psychological game as much as a physical one.
What to Watch Moving Forward
If you're betting on the Chiefs or just following the standings, don't panic. But do pay attention to the trenches. The losses to the Bills and Chargers showed that a physical defensive line can still neutralize a high-flying offense.
- Watch the Injury Report: The Chiefs' depth at wide receiver is thinner than they'd like to admit. One injury to a guy like Rice or Xavier Worthy changes how defenses play them entirely.
- The Defensive Regression: Steve Spagnuolo is a wizard, but even wizards run out of spells. If the pass rush doesn't get home with four, and "Spags" has to blitz, the elite QBs like Allen and Burrow will pick them apart.
- The Schedule Grind: The NFL isn't doing the Chiefs any favors. Their "strength of schedule" is always high because they win the division, meaning they play every other division winner.
To wrap this up, the question of who did the chiefs lose to reveals a league that is finally evolving. The blueprint is out there: play physical, take away the middle of the field, and don't get tricked by the pre-snap motion.
Kansas City is still the team to beat, but they are no longer the team that can't be beaten. If you want to see them lose, watch the teams that win the line of scrimmage and keep Mahomes on the sideline. That’s the only way to stop the locomotive.
For those tracking the rest of the season, keep a close eye on the injury updates for the offensive line. If the left tackle spot doesn't stabilize, Mahomes is going to keep taking hits that no 30-year-old quarterback should be taking. Monitor the "Adjusted Line Yard" stats for the Chiefs' defense too—if they keep giving up 4.5 yards per carry, they won't just lose to the elite teams; they'll struggle against any team with a decent running back and a pulse.