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What you really need to understand about the relationship between Tom Brady and Rob Gronkowski is that they are closer than people know.

The respect Brady has for Gronkowski is strong. Brady has always admired not just Gronkowski's skill, but his almost legendary toughness.

They have stayed in touch over the past few months, one league source explained, and when Brady signed with the Buccaneers, it was only a matter of time before Gronkowski un-retired and joined his former Patriots teammate.

So Brady and Gronkowski reuniting in Tampa Bay- first reported by ESPN's Adam Schefter-is among the least surprising developments of the NFL offseason.

It is also potentially one of the most impactful. This pairing could make the Buccaneers not just the NFC South's best offense, but it could also change the balance of power in the NFL from Kansas City to Tampa Bay.

This is not hyperbole. That's how spectacularly good these two have been together-and can be again.

"Everyone in our division just nodded and said, 'OK, game on, here we go, motherf--kers,'" said one NFC South assistant coach when asked what were his first thoughts after hearing the Gronk news.

Yes, Gronkowski has been injured, but he's also been out of football for over a year. All those aching bones have had a chance to rest. And yes, Gronkowski has lost serious weight, but-and this is breaking news-football players know how to bulk up, and Gronkowski has at least five months to do it.

Brady and Gronkowski are the best QB-TE duo in league history, and it's not even close. Brady is the best quarterback ever, and Gronkowski is the best tight end ever.

The NFC South was already going to be brutal, and Brady was always going to wreck the division, but now that division could be a bloodbath in which defenses are sacrificed to the football gods every week. Hell, every damn day.

We know Brady has obliterated numerous passing records and has reached nine Super Bowls. What is sometimes forgotten is just how spectacular Gronkowski was. When he retired in March 2019, his 91 receiving touchdowns from 2010 to 2018 were the most of any player in that time period. His 12 playoff receiving touchdowns trail only Jerry Rice's 22.

The two don't have to duplicate what they did in New England for another 10 years. They only have to do it for a few years, and they most certainly can.

The Brady-Gronk Bucs won't have an easy path. No one is saying that. That division could end up being one of the toughest in the recent history of the sport. It's starting to look like the old NFC East of the 1980s and 1990s when the Cowboys, Eagles and Giants used to bash the hell out of each other, and the winner of the division would emerge so battle-tested that playing in a Super Bowl was easy.

The South now has the Bucs with Brady, Gronkowski and receivers Mike Evans and Chris Godwin.

The Saints have Drew Brees, tight end Jared Cook, running back Alvin Kamara and receivers Michael Thomas and Emmanuel Sanders.

The Falcons have Matt Ryan, Julio Jones and added Todd Gurley.

The Panthers have Christian McCaffrey and...and...and...Christian McCaffrey.

Here is what the critics will say. Brady is 40-something and learning a new offense, and Gronkowski retired for a reason.

They will say this, and they will be wrong. They will be underestimating two people who should never be underestimated.

Here come the Buccaneers. The league had better watch out.

When's the last time those words were written?

Mike Freeman covers the NFL for Bleacher Report. Follow him on Twitter: @mikefreemanNFL.

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