What went wrong with Bills’ defense in playoff loss to Chiefs? Everything

The Bills deserved to win Sunday night’s AFC divisional playoff game in Kansas City thanks to stellar play from quarterback Josh Allen. Unfortunately for them, they didn’t win because they also had to make a defense against Patrick Mahomes.

The Chiefs outscored the Bills 42-36 in overtime. They did so by tearing apart a Buffalo defense that led the NFL in fewest points allowed (17 per game) and fewest yards allowed (274.6 per game) in the regular season.

Mahomes threw for 378 yards against the No. 1 passing defense (165.9 yards per game). The Chiefs, with Mahomes also leading, rushed for 182 yards against the No. 10 rushing defense (108.6 yards per game).

So what went wrong for the Bills with defensive-minded coach Sean McDermott and defensive coordinator Leslie Frazier, who as of Sunday was having a breakout season calling plays? In short, everything. The Chiefs punted just twice and would have won the game much sooner and less dramatically if they hadn’t gotten cute on some drives that led to field goal attempts, one of which missed.

Allen, who outscored every quarterback in this year’s playoffs, including Mahomes, in both of his games, did his best to save the day with terrific back-to-back TD drives in the fourth quarter. But they didn’t matter much when the Bills allowed the Chiefs to find easy answers.

The epic failure in allowing Mahomes to get the Chiefs into game-tying field goal range in the final 13 seconds of the fourth quarter will be most remembered. However, he was foreshadowed by fundamental problems that played out earlier in the game:

1. Lack of coverage and pressure adjustment

This was by far the worst problem. McDermott and Frazier were expected not to attack Mahomes much. The problem is that the Chiefs were anticipating that. The Bills were so preoccupied with Mahomes’ big-arm passing play that their scheme was too predictable.

Mahomes was adjusted midseason to show more patience against zone defenses. He felt comfortable not forcing things downfield when they weren’t there. The Chiefs were more accepting of taking what they were given and more committed to the race, traditional or not. For NFL Next Gen StatsMahomes avoided the temptation throughout the game to attempt a through ball, something that had never happened in his career.

The Chiefs saw a two-tier safety shell on 92 percent of their offensive snaps. Mahomes responded by going 29 of 38 for 344 of his passing yards and two of his three TD passes against that gaze. That’s a 76.3 completion percentage at 9 yards per attempt and a 120.9 efficiency rating.

Mahomes put up big numbers with his two guys, wide receiver Tyreek Hill (11 receptions, 150 yards, late go-ahead TD) and tight end Travis Kelce (eight catches, 96 yards, game-winning TD). The Bills’ coaches should have realized that the deep gaze of two wasn’t stopping anything and switched to mixing it up with well-timed charged loads. They didn’t just wait until it was too late; never happened.

2. Bad tackle against the run and after the reception.

The Chiefs didn’t need Mahomes to take shots as Hill, Kelce, Mecole Hardman, Clyde Edwards-Helaire, Jerick McKinnon and Byron Pringle slid off initial contact and exploded in the open field after receiving the ball on runs and short passes. There was too much open space and the diversity of players involved often caught would-be tacklers out of position in the second level and in the secondary.

Coach Andy Reid and offensive coordinator Eric Bieniemy, the counterparts to McDermott and Frazier, were smart in designing intermediate plays to maximize the speed and quickness of their playmakers. The Bills’ linebacking corps, a total strength, became a total weakness. With the security devices playing, they were too far apart to help clean up and there was too much space between them. Mahomes had his way with the midfield from end to end. The Bills also couldn’t handle Mahomes’ struggle when they missed passing plays.

3. Critical errors in critical situations

The Bills exacerbated their sloppiness in giving up long plays after the catch by having constant coverage lapses. They made it too easy for the Chiefs on third and fourth down, allowing them to convert 9 of 14 combined chances (64.3 percent). The Chiefs also got two first downs on penalty.

Before Mahomes’ final drive in regulation, the Bills’ ineptitude was on full display as Hill ran into the end zone without resistance. It started when he opened up and continued with him shooting through five defenders to the sideline for a lightning-fast 64-yard touchdown with 1:02 left in the game. That turned a 29-26 lead into a 33-29 deficit in the blink of an eye. The Bills were worn down at the point, and Mahomes continues to have easy reads for his best players against tired pursuers.

4. ‘Prevent’ didn’t prevent anything

The Bills saved the worst for the Chiefs’ final regulation possession. When they should have flipped the switch on the two deep gazes, they instead went the other direction, going into extreme caution with Hail Mary gazes. They were so worried about Hill backing them up again that they didn’t realize Mahomes hadn’t been taking overhand shots the entire game.

Mahomes’ only option with 13 seconds left of his own 25 and needing a field goal was to play for the field goal. The goal was to get inside the Bills’ 40-yard line, or gain 35 yards in two plays. The Bills needed to push harder, give him no more than 20 yards from the sidelines and playoff coverage. Beyond everything else, the Bills didn’t take Hill or Kelce the entire game.

Both the 19-yard shot to Hill and the 25-yard pop to Kelce looked like extended transfers with both receivers turning on jets while keeping an eye on the clock. Mahomes was sacked twice and faced some pressure early in the game, but late against a worn unit, his eyes widened knowing he’d have time to throw against a four-man run.

The Bills thought they had Mahomes figured out at their Week 5 meeting, also in Kansas City. But the final 38-20 in favor of Buffalo was fueled by winning the battle for victory 4-0. Mahomes and Chiefs didn’t turn the ball over in the rematch, taking advantage of low-risk, high-reward plays. Fool Mahomes twice with something he saw the first time? That’s the arrogant, failed mess the Bills put on the field Sunday.