Bill Belichick has watched more game film than probably any other coach on the planet.

So, when he shares an observation from that game film with the masses, you'd best pay attention.

In a rare moment of transparency Thursday, the New England Patriots head coach shared what he's looking for on film while discussing the Buffalo Bills' veteran safety duo of Micah Hyde and Jordan Poyer.

"As a coach or a quarterback, if you look at the safeties, that’ll pretty much tell you 80 percent of what’s going on defensively," Belichick said in his press conference. "Based on their depth, or their rotation – your formation obviously, and then where they go in that formation, and then how deep they are and what kind of angle they’re taking."

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Offenses are always looking for "tells" on the defense to determine what coverage they're in and potentially call audibles. According to Belichick, most of those tells come from the safety position, with just 20 percent of the focus on where the linebackers or defensive ends line up.

But there's a problem Tom Brady and Co. may encounter Saturday with Hyde and Poyer.

"Those guys do a good job of holding that until the last second," Belichick said. "Sometimes they give false keys and start one way then go another way, so that as a quarterback, or as a coach, even if you’re looking at the game and you see something, and you think that’s what it is and your eyes go somewhere else, but then it starts one way and then it goes somewhere else, and then you’ve misread it.


"So, they do a good job of those things, whether they’re blitzing, playing man coverage, playing different zone coverages and different responsibilities in the zones."

One of the best antidotes to a well-disguised defensive coverage is the choice route, where the wide receiver has the option of running multiple routes depending on how the secondary moves after the snap.

But a choice route relies on an inherent trust between quarterback and wide receiver that the latter will end up in the right spot.

That trust hasn't exactly been abundant recently in New England, where rookies N'Keal Harry and Jakobi Meyers and new addition Mohamed Sanu have struggled to get on the same page with Brady.

The Patriots quarterback ranks 29th in the NFL with a 60.1 completion percentage, and a good portion of those incompletions were the result of Brady throwing the ball to one spot and his receiver being in another.

Against an elite defense like Buffalo -- which is allowing just 190.5 passing yards per game and holding QBs to a 61.8 completion percentage -- Brady will need his receivers to pick up on the Bills' disguises and end up in the right spots Saturday.

That, or Brady and Belichick will need to win the chess match with Buffalo's safeties on their own.

"Sometimes if the safeties disguise and the linebackers aren’t tied in with it, you’ve got all these guys over here together -- somebody’s going to have to go somewhere else," Belichick added. "So it’s, 'OK, they’re trying to disguise it. We can see they’re trying to disguise it.' "