Every offseason, teams across the league make changes and tweaks to what they run in hopes of emerging even better into the new season.
For the Arizona Cardinals, that was a change in coverage.
Under defensive coordinator Nick Rallis, the Cardinals ran mostly a Cover 3 zone last season, which was among the highest usage in the league.
In 2025, Arizona changed things up and have now switched to a heavy Cover 4 zone - and they use that specific look more than any other team in the NFL.
Arizona's 28% usage of Cover 4 this season ranks first, according to Football Insights. The team still heavily uses Cover 3 as a secondary coverage:
Team coverage rates through Week 6
— Football Insights (@fball_insights) October 14, 2025
Via @FantasyPtsData pic.twitter.com/VtRrdAOtdj
Arizona is also one of 13 teams to use man coverage at a rate of 20% or less through the first six weeks of 2025:
The drop-off in coverage usage for the Cardinals is quite steep after those two looks:
“Probably who we're playing, that goes into that. Where you want to play coverage structure wise," said Cardinals coach Jonathan Gannon when asked about the change.
"We made some tweaks to Cover 3 this year too. That’s a good question, it’s a long-winded answer. I think whatever you're playing—doesn't matter what you're playing—I'd like to see an uptick of execution in the back end and that's everybody collectively. We have a couple staples and then get to them different ways but depending on who you're playing really goes into what you're kind of leaning on.
"I always say, ‘If you kind of have one shell that's the staple going into the week and you want to mix two other ones—you have one post-close, you want to mix two other ones.’ I think one of the ways to affect the quarterback is not just play a couple coverages, so we try to be multiple in that aspect. I'd like to see us play them a little bit better.”
Gannon has always been a big proponent of limiting explosive plays - and Cover 4 does just that.
With four defenders - two safeties and two boundary corners - dropping deep, it's awfully tough for teams to push the ball downfield for big yards.
If you're looking to limit explosives (plays of 20+ yards), you found your coverage.
On the other side of the coin, however, is the underneath game. With heavy commitment to the deep part of the field, Cover 4 can be exposed with only three defenders underneath.
If you've seen Arizona's late-game defensive drives, you've also seen quarterbacks carve up the middle of the field and intermediate slot/seam spots.
It's always a battle of philosophies in the league. The Cardinals' defense is certainly not the worst unit in the league despite their fourth quarter struggles, though if Arizona hopes to rebound from their awful 2-4 start, they'll need to find their footing. Quickly.
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