The #1 story of NFL free agency 2021 has been the New England Patriots going on a massive spending spree. We’re currently two days into free agency–technically it’s the “legal tampering period” but teams and players can already agree to deals, so free agency has de facto begun–and the Patriots have already signed the following free agents (accurate as of 10:30pm, Tuesday March 16):

• Hunter Henry
• Jonnu Smith
• Matthew Judon
• Nelson Agholor
• Kendrick Bourne
• Henry Anderson (DL)
• Jalen Mills (DB)
• Davon Godchaux (DL)
• Trent Brown (OT–acquired via trade)

They also resigned Cam Newton, Deatrich Wise (DL), Carl Davis (DL), and Justin Bethel (DB).

The Patriots traded away OL Marcus Cannon, lost OT Joe Thuney to the Chiefs in free agency, and also lost S Terrence Brooks to the Texans via free agency.

They’ve still go 15 players from last year’s team who are currently free agents (list at link above). It remains to be seen what they do with them.

Obviously Belichick’s free agent signing frenzy has turned a lot of heads in the sports world. It’s basically been the top story in sports media today.

One talking point I’ve seen a lot of media people pushing is that Belichick is acting out of desperation after watching Tom Brady win a Super Bowl in his first season with the Bucs. Belichick is not known to be a big free agency guy, and in fact over the past two days, he’s spent more money on free agents than he did over the prior 10 seasons combined.

So naturally a lot of people are saying he’s reaching, he’s desperate, he doesn’t know what to do, and so he’s behaving erratically and uncharacteristically as a result.

But NFL fans should know by now not to underestimate Bill Belichick. The guy generally knows what he’s doing. Sure, he’s been pretty terrible at drafting offensive skill players historically, but he’s managed to build 6 Super Bowl Champions in spite of that.

There’s a reason Belichick is spending like crazy right now, and it’s not because he’s panicking.

The first major reason is that the NFL salary cap went down by $15.7mil for this upcoming season. It’s currently at $182.5mil after being $198.2mil in 2020.

This is a big deal. This is the first time in over a decade that the salary cap has gone down from one year to the next. And the $15.7mil decrease is a big drop: the 2021 salary cap is now lower than it was not only in 2020, but also in 2019 ($188mil).

The sharp decrease in the salary cap means that a lot more players got cut this year than otherwise would’ve been. There were a lot more cap-casualties this year than any other year, meaning a lot of guys who otherwise wouldn’t have been available were available.

So teams with a lot of cap space this year were and are in prime position to scoop up guys who probably shouldn’t have been available if not for the pandemic leading to a $3 billion decline in league revenues.

The Patriots were one of those teams that had a ton of cap space and were able to capitalize. They came in to free agency 2021 with $68.5m in cap space, which was the third-most in the league behind the Jaguars ($73m) and the Jets ($69m).

This explains why the Jaguars and Jets have been signing a lot of players as well, although neither team has gone as crazy as the Patriots have thus far.

Nearly a third of the league came into free agency 2021 with negative cap space. This is why you’ve seen so many guys restructure their deals lately.

According to USA Today, half the teams in the league had less than $15m in cap space this year. This means that just a few teams basically had the whole pool of free agents to themselves, and the Patriots were one of those few teams.

So in light of this information, it makes total sense why the Patriots went on such a signing binge: they were one of the few teams that actually could.

On top of all this, you also have the fact that the reduced cap means free agent deals signed this year are smaller than they otherwise would’ve been. The Patriots are getting good deals on all these guys, especially when you consider that the salary cap is expected to go back to normal for 2022, as the pandemic-caused revenue drop was a one-off event and not some long-term, secular decline in NFL revenues. Had the pandemic not happened, the cap probably would’ve gone up this year.

These free agent contracts that the Patriots are signing right now are, over the next couple years, going to prove to be great deals.

Bill Belichick is a shrewd operator. He put himself in prime position to take advantage of the unique salary cap circumstances caused by the pandemic.