Each week throughout the season, we will break down ESPN's NFL Power Rankings from the perspective of ESPN's Football Power Index (FPI) to determine which teams are ranked too high, which too low, and why.
As a reminder, the ultimate goal of the NFL FPI is to measure team strength and project performance. Each season, some teams are better than their records suggest and others are overrated based on their win totals. This is often a result of many close wins/losses, luck or schedule. Because FPI looks at a team's per-play efficiency rather than its win total, it can uncover the teams that are most overrated and underrated and project which teams will be strongest.
For more on FPI and how it's calculated, please read this explainer. For FPI's complete rankings, click here.
Overrated teams
FPI ranking: 11
Power Rankings rank: 4
Reason they're overrated: Offensive inefficiency.
With an NFL-high 14 turnovers forced and 22 sacks, the Broncos lead the NFL in defensive efficiency -- a per-play measure of a unit's contribution to scoring. There is no doubt that Denver's defense is elite, but through five weeks, its offense is more of a liability than an asset.
Denver has eight offensive touchdowns, which is tied for the second fewest by a team to start 5-0 since the 1970 merger (according to the Elias Sports Bureau). The Broncos rank 28th in offensive efficiency with a rating of 32.3 out of 100. For reference, no team that played in the Super Bowl in the past six seasons had a below-average offensive efficiency, and 10 of the 12 teams ranked in the top 10.