AVENTURA, Fla. — The Chiefs’ 2018 season ended with Patrick Mahomes on the sideline when Kansas City failed to stop Tom Brady and the Patriots in overtime of the AFC Championship.

That was when the Chiefs began their rebuild of their defense. Andy Reid fired longtime defensive coordinator Bob Sutton and replaced him with Steve Spagnuolo, switching from a 3-4 to a 4-3. They traded for defensive end Frank Clark from the Seahawks and signed free-agent safety Tyrann Mathieu.

The changes did not immediately work. In the first 10 weeks of the season, they allowed 23.9 points per game, 19th in the NFL. They gave up 29 touchdowns (23rd) and ranked 14th in takeaways.

Then, something clicked.

Since November, the Chiefs defense has been on a roll. In the final six game of the regular season, they gave up 11.5 points per game, the fewest in the league. They allowed seven touchdowns, an NFL low and had 10 interceptions, tied for No. 1.

In the playoffs, the defense frustrated Texans quarterback Deshaun Watson and slowed down Titans running back Derrick Henry.

Everyone knows about Mahomes and the high-flying Chiefs offense, but it might be this underrated defense that is the difference in Super Bowl LIV on Sunday.

“We’re ready to get on this stage and show the world that we deserve to be here as a defense,” Mathieu said.

Chiefs defenders said the change came midseason because they got more comfortable with Spagnuolo’s defense and them challenging each other to take pressure off of Mahomes.

“Honestly, it was us,” defensive lineman Derrick Nnadi said of the difference. “We had to just realize what we had to do as a team, as a defense. We just said we can’t keep relying on Pat to save us. That’s not going to get us far. It wouldn’t have gotten us where we are right now. We really had to buckle up and just play. We had to keep pressuring as a defense and take over the game.”

The Chiefs forced four takeaways in a 24-17 win over the Chargers in Week 11, a sign that things were changing. They kept three of their next five opponents out of the end zone. In the playoffs, the Chiefs sacked Watson four times and held the Texans to 94 yards rushing. In the title game, they held Henry to 69 yards and a touchdown, ending his dominance.

The Chiefs defense, which bottled up Derrick Henry in the AFC title game, is looking to make its mark in Sunday's Super Bowl.
The Chiefs defense, which bottled up Derrick Henry in the AFC title game, is looking to make its mark in Sunday’s Super Bowl.Getty Images

“I think ultimately we’re just playing together as a team,” Mathieu said. “I think we have a lot of talent on our defense. I think a lot of guys are buying into that. I think a lot of guys are starting to believe in their abilities. We’ve been playing like that.”

The challenge on Sunday will be stopping a 49ers rushing attack that has been relentless in the playoffs. The run defense was the Chiefs’ weakness this season, but it has drastically improved lately with their performance against Henry the latest example.

Still, the Chiefs know the 49ers’ rushing attack presents a different challenge than the Titans’.

“It’s totally different,” linebacker Reggie Ragland said. “Derrick is all about coming downhill. These guys here, they’ve got all the speed in the world to bounce and outrun, setting the edge. We have to do a great job of setting the edge. Guys have to do a great job of filling the holes and the gaps.”

Mathieu said the Chiefs have not forgotten the early criticism they received.

“There’s always going to be criticism. It’s the NFL, especially when you play with an offense that’s as high-powered as our offense,” Mathieu said. “I think a lot of the criticism is going to fall on the defense. We’ve been embracing it. We’ve been accepting it. We’ve been stacking our bricks. We haven’t forgotten anything that anybody said. We’re highly motivated.

“We feel like we’ve got one more game to prove our point.”

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