At times, it was a matter of great coverage by a much-improved Dolphins secondary against a mediocre New England receiving corps.
And at other times, it was a matter of a well-disguised blitz, such as when Yeremiah Bell came in free from the side to nail Brady and cause a fumble that Bell himself recovered.
Actually, the best example of a brilliant disguised blitz came a few plays earlier when Bell started on the outside, then looped toward the middle to come in free on Brady. That play ended badly because Bell was called for roughing the passer when he tackled Brady around the waist after the pass had been thrown, but it was a good illustration of a defense that was confusing Brady -- and more specifically his blockers.
It was very telling to see Brady yelling at his offensive linemen during the game on Sunday, even though he wouldn't point fingers afterward.
The Dolphins brought some different blitz packages to the stadium on Sunday, and that made a big difference. And so apparently did their studying Brady's protection calls to his offensive linemen, which helped them adjust where they would be coming from.
But it was more than just a great scheme because the Dolphins have done this to Brady before.
Check out this stat: Since taking over as New England's starting quarterback in 2001, Brady has been held under 100 yards only four times. All four games were against the Dolphins.
One came in Brady's second start in 2001 when the Dolphins pounded New England, 30-10. The second came in 2004 when Brady threw for only 76 yards, but had two touchdowns in New England's 24-10 victory. The third came in last year's season finale when Brady was pulled early because the Patriots' playoff seeding already was set.
Even in the first meeting this season, Brady threw for only 140 yards. But as he so often has done during his career, he made enough plays to lead his team to victory.
On Sunday, that wasn't going to happen. It was weird watching the game because the score was 6-0 until midway through the third quarter and as dominant as the Dolphins defense was, you still had the feeling that Brady would find a way to pull it out.
But the Dolphins defense never gave him a chance. It got so bad for the Pats that they resorted to a gadget play with Kevin Faulk taking the snap from shotgun formation and throwing back to Brady, who then threw downfield to tight end Daniel Graham.
The play worked to perfection, except that Faulk's throw to Brady went forward, making Brady's pass to Graham an illegal forward pass.
Three plays later, Bell sacked Brady and forced the fumble.
As great a victory as it was, the Dolphins still won't make the playoffs. But they sure could offer some great advice on how to defend Brady to whoever does face the Patriots in the postseason.