Mommas make sure your kids grow up to be giant hulking left tackles, because they will end up being really rich if they do. The latest proof is former 49ers and Patriots tackle Trent Brown, who helped the Pats win a Super Bowl, left in free agency and just got VERY rich while signing with the Oakland Raiders immediately at the start of the NFL's legal tampering period on Monday. 

Brown, according to multiple reports, signed a four-year deal that will get him an absurd $66 million with $36.75 million guaranteed. That is an incredible amount of cheese for a guy who last offseason was shipped out of San Francisco and to New England for a swap of mid-round picks. 

The Pats gave up No. 95 overall to the 49ers in exchange for Brown and No. 143 overall, meaning the Pats basically moved down 40 spots in the draft to acquire Brown. It didn't really raise eyebrows, but Brown was critical to New England's Super Bowl run, filling in for the injured Isaiah Wynn (drafted out of Georgia last year) and playing left tackle, more than capably protecting Tom Brady's blindside and helping to shore up one of the best rush offenses in the NFL.

Brown said he would "love" to stay in New England, but the Patriots ultimately declined to use the franchise tag on the tackle, allowing him to walk into free agency. 

Once that happened there was no way he was coming back: there is too much demand for offensive lineman on the open market and too much money available to teams who need tackles for it to happen. 

This is now the second straight year that Brady's left tackle has walked into the free agent market and landed a monster deal, as Nate Solder left New England for the Giants and a massive contract on the open market last offseason.

What it means for the Raiders

Oakland now has the awkward scenario of moving last year's first-round pick, Kolten Miller out of UCLA, to right tackle. This just 10 days after Jon Gruden came out and said he believed Brown would be a Pro Bowl left tackle for seasons to come. So either Gruden was lying about Miller OR the Raiders just gave the most money to an offensive lineman in the history of football to a right tackle. Either one isn't ideal.

But you can clearly see how the Raiders are approaching the 2019 season and it's with GUSTO. Gruden wasn't happy with how last season went and he's not willing to stand back and lose again this coming season, even though it looked like, with his monster 10-year contract, he might be willing to lose until the team got to Las Vegas.

Instead, Oakland has now traded for Antonio Brown and given a left tackle $66 million in free agency over the last 48 hours. Those are big moves, and it might not be all. There are a lot of rumors about the Raiders wanting to sign Le'Veon Bell as well, although there may be some cash issues they have to deal with in order to get the other former Steelers star in the building. 

One thing worth watching is how the Raiders handle the draft situation. They have four picks in the top 35 -- will those be utilized to mostly fill voids on the defensive side of the ball? Will one of them go to another offensive playmaker? Will the Raiders draft a quarterback (Kyler Murray at No. 4 perhaps)? If they don't take a quarterback, it would appear that Gruden is either a) building around Derek Carr or b) eying a QB in the 2019/2020 drafts or c) both. 

Carr is a monster winner in the first 24 hours of free agency, as the quarterback got a top-tier wide receiver and an expensive piece added to his offensive line. 

Why the Patriots win big

But don't sleep on the Pats either. New England didn't pay much for Brown's services and his ROI was through the roof. The big win, though, is that New England is likely to end up scoring a third-round compensatory pick for letting Brown walk into free agency as a result of his contract and all the playing time that he ends up getting in Oakland. 

That pick should be in the No. 100 range, meaning it will actually be more valuable than whatever they actually gave up (No. 143 minus No. 95).

Which is to say that the Patriots understand the system better than anyone else and they just worked within the structure of the system perfectly. They moved down about 45 spots in the draft to acquire Brown, they plugged Brown into their offensive line system, they made him look really good, they let him walk in free agency and now they will create a top 115 pick in the draft out of thin air. They'll probably get two of them with Trey Flowers looking he will walk as well. This is really good work by the Patriots and the type of thing they do every single year and somehow no one else is disciplined enough to follow their path (the Rams are actually pretty good at it too). 

New England is losing a good player, but they're not overpaying for a tackle and they're getting a free pick in the process. The Bill Belichick Destruction Machine rolls on.