Dallas just engineered one of the most dramatic defensive turnarounds in recent history

The list of teams that have turned their defense around quicker than the 2021 Cowboys is short.

Since 2001 there have been 331 teams that finished as a below-average defense in the NFL. Another 251 have ended as a bottom twelve defense, which means that hundreds of teams since 2001 have attempted to right the ship defensively.

While prioritizing defense will assuredly result in at least marginal improvement, especially if the defense was historically bad the year prior, few have managed to jump from one of the worst in the NFL to one of the best in the span of one year. Dan Quinn and the 2021 Cowboys are one of them.

Dallas just engineered one of the most dramatic defensive turnarounds in recent history

There is little use in rehashing 2020 because it was a horrific year for the defense. Consider that when the opposing punter walked onto the field against the Cowboys in 2020, there was an equal chance he was holding the ball for a PAT attempt as he was to actually punt the ball.

Heading into 2021, most Cowboys fans expected improvement on the defensive side of the ball. Adding a few contributors in free agency, hiring Dan Quinn, and using almost all of their draft capital on defense should improve the output.

Little did Cowboys fans know the defense was about to become a top-five unit in the league and anchor this team over the second half of the year.

Now, by EPA per play, teams that finish in the bottom half of the NFL commonly move up around six spots in the NFL rankings the following year. Teams that end as a bottom-twelve defense average a 7.5-spot ranking improvement.

And per rbsdm.com, Dallas finished as the 23rd ranked defense in 2020 when you exclude garbage time. Most fans likely assumed that the Cowboys would end roughly middle of the pack in 2021 due to their focus on defense in the offseason.

But in 2021, Dallas jumped to the third-ranked defense in the NFL by EPA per play, including the third-best coverage unit in the league. That twenty-ranking spot improvement over 2020 has only been eclipsed 27 times since 2001.

While 27 other teams jumping more than twenty spots in the rankings might appear to diminish what the Cowboys did, consider where Dallas started. Because of those 27 teams, nearly all of them finished as a bottom-five defense the year prior. Among the teams that improved more than Dallas, their average finish was the fourth-worst defense in the league the year before the jump. And not a single one of them was better than 24.

But in 2020, Dallas was ranked 23rd, and they jumped to third in 2021. Their EPA per play improvement of .161 is the 13th biggest leap of any team since 2001.

This was a historic turnaround, and while it wasn’t the best in recent history, there have only been a handful of defenses that improved more than the Cowboys did over the past year.

Over the past 21 seasons, the Dallas defense has finished in the bottom half of the NFL 13 times. Yet, despite how bad the Cowboys’ defenses have been, the 2020 defense was the third-worst since 1999. However, finishing as the third-best defense in 2021 is the highest finish the Cowboys have seen over the past twenty years.

Meaning that in one year, the Cowboys transitioned from one of the worst defenses in recent history to arguably the best that Dallas has had since the 1990s. That improvement is unprecedented, and while it isn’t the most drastic in NFL history, the turnaround cannot be overstated.

The obvious argument against this will be that the Dallas defense succeeded due to turnovers and a week schedule. However, that is not true because:

1. Excluding turnovers, Dallas drops from the third-best defense in the NFL to the sixth-best by EPA per play. The coverage EPA per play plummets from third to fourth. Overall, while the Cowboys’ defense did generate turnovers, they were still a top-ten defense without the takeaways.
2. The 2021 Cowboys faced the fifth most challenging schedule in the NFL last season, according to TeamRankings.com. And this is confirmed by Football Outsiders placing the Dallas defense as second in the NFL by DVOA, which incorporates the difficulty of schedule.

Simply put, the defensive improvement from 2020 to 2021 was incredible, and there have only been a handful of teams that have accomplished what the Cowboys just did. Even considering how volatile defenses can be, the turnaround was entirely unpredictable.

There is a lot of credit to go around. Dan Quinn, Micah Parsons, and even players such as Jayron Kearse, Osa Odighizuwa, and Randy Gregory playing an entire season were all a massive reason for the change. We shouldn’t attribute this turnaround to one person only because Dallas wouldn’t have accomplished this without all eleven men on the field plus the coordinator leading them all.

But what the Cowboys accomplished on defense this year was incredible. Even without the 24 turnovers, this was one of the best units in the league. If there is one source of optimism for next year, both the coordinator and young pieces will be returning to the defense in 2022. Who knows what another offseason with Dan Quinn will lead to.