From best to worst: Vikings getting torched by long passes at alarming rate

The Vikings did a lot of things well on defense in 2017, when a unit ranked No. 1 overall in both points allowed and yards allowed was the backbone for a 13-3 regular season.

One thing Minnesota did particularly well a year ago was avoid allowing opponents to make big plays in the passing game. The Vikings allowed 35 pass plays of more than 20 yards a season ago — fewest in the NFL. And they allowed just five pass plays of 40 yards or more — one of only six teams that allowed five or fewer.

Limiting big plays went hand in hand with other strengths, such as getting off the field on third down at an historic rate.

Conversely, though with the same sentence structure, the Vikings have done a lot of things poorly on defense so far in 2018, with a unit ranked in the bottom half of the NFL in both yards and points allowed contributing to a 1-2-1 start.

And one thing Minnesota has done particularly poorly this year is that the Vikings are allowing a ton of big passing plays.

They've already been gouged for 17 pass plays of at least 20 yards — close to half as many as last season in one-quarter of the games. That's tied for fifth-most in the NFL. And they've already allowed five pass plays of 40 yards or more — tied for most in the NFL and the same number they gave up in 16 games last season.

While I don't have a definitive answer as to why this is happening, we batted around plenty of theories about the defensive struggles in general this week on the Access Vikings podcast.

On the second point, the Vikings have been so solid and so hard to sustain drives against — here again that third down toughness comes into the equation — that quick strikes and big plays might be a better method by which to attack them.

The Rams, for instance, had four touchdown drives that were five plays or less on Thursday. They didn't face a single third down on any of those drives and never had anything longer than 2nd-and-5 in second down situations.

It will be interesting to see how — and if — Vikings coach Mike Zimmer can schematically correct what is going on.