Sgt. Adam Grossman says the 42-year-old man was leaving the stadium in East Rutherford on Sunday at around 4 p.m. when he fell over the side of the escalator. It's not clear what caused him to fall.
Grossman says the man fell about 21 feet and landed on a metal stage.
The man was airlifted to Hackensack University Hospital and was in critical condition Sunday night. Grossman says the investigation is ongoing.
The Giants beat the Redskins 27-23 with a late 77-yard scoring pass from Eli Manning. More than 80,000 fans attended the game.