2. Denver Broncos
The Denver Broncos, for the second consecutive season, set a franchise record in sacks as a team. That is a preposterous stat. The Broncos' 68 sacks this past season challenged the vaunted Chicago Bears' record in a single season of 72, a record that was set all the way back in 1974.
They didn't end up breaking that record, but there is not a team in the NFL that gets after the quarterback like the Broncos. They not only have one of the league's best and deepest groups of pass rush threats, but they have arguably the best secondary in the league, led by reigning Defensive Player of the Year Pat Surtain II.
The Broncos' main weakness defensively this season has been an inability to consistently generate takeaways. Going into Week 18, they had just 11 takeaways as a defense. They got a couple off of the Chargers in that final game, but for a defense that gets to the QB so frequently, it's a shocker that this team wasn't among the league leaders.
They finished the year ranked 3rd in points allowed, 2nd in total yards allowed, #1 in the red zone, and #2 on third downs. The Denver defense is Super Bowl-caliber.
1. Houston Texans
Although there are a number of great defenses in the NFL playoffs separated by very thin margins over a large sample this season, why do the Houston Texans give off "cheat code" vibes on that side of the ball?
The Texans had an incredible season ranking 1st in the league in yards allowed, 2nd in points allowed, and tied for 7th in sacks. They were the 6th-best third-down defense in the league, and they forced 29 total takeaways, second only to the Bears among defenses left in the playoffs.
There isn't really a weakness to discuss right now with this Houston defense. They are phenomenal in every way possible. It requires a truly special effort offensively to beat these guys, which hasn't happened in a long time. They've won nine games in a row, and the last team to beat them was the Denver Broncos back on November 2.