The Pittsburgh Department of Public Safety said police and emergency service personnel were alerted after a male spectator fell around 4:45 p.m., shortly after the end of New York's 24-20 victory over the Steelers.
Paramedics administered care on site before the victim was transported to the hospital in critical condition. He died shortly thereafter. The Allegheny County medical examiner's office identified him Monday as 27-year-old Dalton Ryan Keane of Monaca.
"We are aware of an unfortunate incident that occurred inside Acrisure Stadium today," the Steelers said in a statement. "We are working with local authorities and helping their investigation into the matter. We are sending our thoughts and prayers to the guest's family."