Super Bowl 36: 1:21 left on the clock, the Patriots drive 53 yards in nine plays to set up Vinatieri's game winning field goal.
Super Bowl 38: 1:08 on the clock, the Patriots drive 37 yards in six plays to set up Vinatieri's game winning field goal.
Super Bowl 44: 6:52 on the clock, the Patriots drive 64 yards in ten plays finished by a 3 yard touchdown catch by Edelman to take the lead.
Super Bowl 51: 3:31 on the clock, the Patriots drive 91 yards in ten plays finished by a 1 yard touchdown run and a 2 pt conversion to tie the game. They follow it with an eight play, 75 yard drive to win the game in overtime.

Brady made those drives happen, not Belichick. As for "tough defenses" the only two losses the Patriots had in Super Bowls happened when the defense folded like a deck of cards in the final minutes leaving Brady with hardly any time left on the Patriots final drive. Heck, they only won SB44 because the Seahawks decided to get fancy and call a pass play on the Patriots one yard line. Seattle went 79 yards in 1:42 prior to that play, some "tough" defense.

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