The penalty - which was initially called on Carolina's Luke Kuechly for interfering with Rob Gronkowski in the end zone - would have given the Patriots the ball on the one-yard line with a final chance to win the game.
But the flag was picked up and the official declared the game over.
After the game ended, he chased down the officials and berated them on their way into the tunnel. The ESPN cameras caught him apparently saying, "That's f***** bull," before cutting off his microphone.
Back-up QB Ryan Mallett got in on the action as well:
Here's the controversial final play.
Gronkowski basically gets tackled. The official also didn't explain why the flag was picked up, so Brady has some legitimate reason to be mad here (via @BuzzFeedSports):
Brady was more subdued in his postgame press conference, saying the final play was his fault for not making a better throw.
A win would have given the Pats a commanding two-game lead in the race for the No. 2 seed (and the all-important bye) in the AFC playoff race. So this could end being a meaningful no-call.