A representative of his funeral home in North Carolina confirmed his death, the cause of which is unknown.
Guglielmi was drafted by the Redskins with the third pick of the 1955 NFL Draft and played intermittently for Washington over four seasons (1955, 1958-60). He would go on to play a total of seven seasons in the NFL with the St. Louis Cardinals, New York Giants and Philadelphia Eagles.
In his rookie season, he won all three games he started in Washington, throwing for two touchdowns and 242 yards. His career highs all came in his final year with the Redskins, where he threw for 1,547 yards and nine touchdowns.