Tom Brady is walking out the door, taking 20 years of institutional knowledge with him. But Bill Belichick is the master of preparing his team and punishing opponents. There's no reason that can't continue.

While Tom Brady’s departure allows us a brief moment to imagine an AFC East legitimately in contention for the first time since the George W. Bush presidency, let’s not forget that the rest of the brain trust behind the greatest dynasty in American sports history is still intact.

Do we really think that Bill Belichick is all of a sudden fragile?

The best part about Brady's testing free agency and ultimately playing the 2020 season away from New England is that it can finally help us answer the chicken-or-the-egg question we have had about the coach and quarterback in Foxborough for the better part of 20 years. Did Brady make Belichick great, or was the system he played in more responsible? The likely truth is that it was kismet: a coach who found a quarterback willing to put in the Herculean efforts that he expected of himself. The pair sharpened one another and created something monumental.

But the sub-truth is that Belichick could win again without Brady.

Putting aside for a moment the possibility that any quarterback may squirm at the chance to replace the greatest player in NFL history—a person eternally beloved in a stadium that even contains a facility for his own lifestyle brand—would it be truly stunning to see Andy Dalton win 10 or 11 games under center? Cam Newton? Teddy Bridgewater? This is not suggesting that any of them are as talented as Brady, even a post-40 Brady, or that any of them could gain a master’s degree in Josh McDaniels’s offense that would replace the institutional knowledge walking out the door.

However, people might forget why players routinely take less to play for the Patriots. Working with Belichick is like playing poker with the pocket camera on. Stephon Gilmore once told me that Belichick pulled him aside before a windy game one Sunday and cautioned him on how the ball speed on deep throws would lag just so, and how he should trail the wide receiver on longer plays. Kyle Van Noy said that it’s truly epic getting to wear the “green dot” on defense with a direct connection to Belichick’s thoughts and wisdom.

This is a coach who has managed to break down and throttle the rest of the NFL for 20 seasons by grinding away at their weaknesses. The Patriots look like three or four completely different teams every year. None of that will change just because a quarterback closer to replacement level is under center.

Back in 2010, when the Patriots lost to the Jets in the divisional round of the AFC playoffs, it struck me how perfect everything needed to be for us to even consider the remote possibility that the guard was changing. A game plan designed, in part, by heady safety (and now Wisconsin defensive coordinator) Jim Leonhard. Perfect performances from veteran defensive linemen. A career game from Mark Sanchez and some uncharacteristic floundering in the pocket by Brady. That’s how you beat the Patriots over the last 20 years—perfect moments and game plans, perfect quarters and some uncharacteristic stumbles on the other side.

They are still as close to perfection as any team in football and need to be treated as such.

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