Rating the NFL's most improved teams: Reasons behind the rise of the Cowboys, Cardinals, Chargers and Bengals

Ryan Clark: Mike McCarthy is the worst coach on the Cowboys (1:15)

Ryan Clark says Mike McCarthy is the worst coach the Cowboys have and believes Dallas would be better off without him. (1:15)

Let's evaluate the four teams whose chances to make the 2021 NFL playoffs have improved the most since the start of the season, as measured by ESPN's Football Power Index (FPI).

A lot can change over the course of six weeks, and in a league in which the Titans can lose to the Jets and beat the Bills in the course of two weeks, it's not always easy to contextualize the big picture. I'll try to do that here to get a sense of what has happened to these four breakout teams and what might change for them, both positively and negatively, in the weeks to come.

Let's start with the league's lone undefeated team, which you likely expect to be on this list:

Jump to a team:
Bengals | Cardinals
Chargers | Cowboys

Arizona Cardinals (6-0)

Preseason FPI playoff chances: 32.2%
Current FPI playoff chances: 99.2%
Difference: Plus-67%

The Cardinals! Projected in most places to be the worst team in the (admittedly very good) NFC West, Kliff Kingsbury's team is a game and a half up on the Rams and way out front of the 49ers and Seahawks through six weeks. Only two of its games were close, with Arizona beating the 49ers 17-10 and topping the Vikings 34-33 when Minnesota kicker Greg Joseph missed a last-second field goal. The teams the Cardinals have beaten have gone a combined 16-12 when they haven't faced Arizona this season, so it's not as if they've played an easy schedule, either. This team is legit.