The Giants' comeback was so big that only three teams have ever rallied from a 25 point deficit in the fourth quarter in NFL history. None have come back from 26 points. Yes, it was the largest fourth quarter comeback in NFL history. Don't get too excited, it's a preseason game and doesn't count.
The Giants engineered one of the greatest comebacks in the history of football on Saturday scoring 27 points in the fourth quarter to beat the Colts 27-26. It was a preseason game, and didn't count, but it's so rare that it even perked the interest of Football Outsiders.