NFL Week 5 Defense Rankings

• 49ers take No. 1 spot: San Francisco is allowing the lowest EPA per play mark (-.229) in the NFL through five weeks.

• Bills, Cowboys round out top three: A banged-up Bills secondary is still performing well, and an elite Cowboys defensive line is posing problems for opposing offensive lines.

• Browns struggling despite on-paper talent: A formidable pass rush hasn't been enough to balance out a shaky secondary.

Estimated Reading Time: 18 mins

1. San Francisco 49ers

EPA/Play Allowed: -0.229 (1st)

The 49ers have allowed the fewest points per game (12.2) and are No. 1 in expected points added (EPA) allowed per play. They also lead the league in EPA allowed per passing play, at -0.225. They’ve got an incredible pass rush, and they’ve done it without several key players on the defensive line. The groin injury to Nick Bosa, whose 89.6 PFF grade ranks fifth among 125 qualifying edge defenders, could be a major issue for the 49ers going forward, but this has been the NFL’s best defense through five games.

2. Buffalo Bills

EPA/Play Allowed: -0.182 (2nd)

It almost feels unfair to rank the Bills at No. 2, as their defense has been outstanding this season. They've allowed just 12.2 points per game and a combined seven points in the second half of contests this year. They are slightly worse in expected points added allowed per play than the 49ers, but that also has to do with the fact that the Bills have played better offenses to date.

Either way, this is an elite defense that can win games by itself due to its pass rush and overall depth. Both Boogie Basham (89.9) and Von Miller (89.2) rank top six among edge defenders in overall PFF grade this season, and Matt Milano (90.4) is the highest-graded off-ball linebacker. Once the Bills' secondary gets healthier, this might be the best defense from top to bottom in the NFL.

3. Dallas Cowboys

EPA/Play Allowed: -0.142 (6th)

The Cowboys just put together back-to-back dominant performances, giving up 20 combined points to the Commanders and the Rams. Dallas ranks second in sacks (20) and is led by superstar edge defender Micah Parsons. What makes the Cowboys unique is their depth on defense — they currently have eight players on defense with an overall grade of 69.5 or better (min. 100 snaps). The unit is without a clear weakness, and their pass rush might be the best in the NFL. The Cowboys also rank seventh in expected points added allowed on passing plays, at -0.155.

4. Denver Broncos

EPA/Play Allowed: -0.162 (3rd)

The Broncos' defense is the only reason the team has had any success this season. Their pass rush has been incredible, as Bradley Chubb and Randy Gregory are off to the best start of their careers. Both have 19 pressures and 80.0-plus pass-rushing grades through five weeks.

The Broncos are battling some injuries in the secondary and to Gregory, but this is still one of the best units in the NFL. Denver also ranks fourth in expected points added (EPA) allowed on run plays, behind only the Raiders, Colts and Saints. If the Broncos can turn things around this season, it'll likely be due to their defense continuing to hold opponents under 17 points per game.