This is the act after the ball has been fumbled. Once recovered by the defensive team they take the back and score a touchdown.
The Miracle at the Meadowlands happened in a 1978 game between the New York Giants and Philadelphia Eagles. The Giants were leading the game and attempting to run out the clock. When the botched handoff to the fullback led to a fumble, Eagles cornerback Herman Edwards picked up the ball and returned it for 6 points, winning the game for the Eagles.