James Michael Curtis (March 27, 1943 – April 20, 2020), nicknamed "Mad Dog" or "the Animal," was an American professional football player for the Baltimore Colts, Seattle Seahawks, and Washington Redskins.

[2] A report card filled with three F grades, two Ds, and an A in physical education had an invigorating effect, Curtis noted in his 1972 memoir: "It was one of the best things that ever happened to me.

Players had significant financial leverage in this period, with two teams competing for their services, and Curtis received a healthy two-year contract to play for the Colts.

[7] During his rookie season with the Colts, Curtis was listed third on the depth chart at fullback, playing behind Tony Lorick and Jerry Hill.

[10] Curtis, Ray May, and Hall of Famer Ted "the Mad Stork" Hendricks formed a potent linebacking corps from 1970 to 1973,[1] helping the team to victory in January 1971 in Super Bowl V against the Dallas Cowboys.

That 1970 season was one of Curtis' finest, in which he had five interceptions, including a key pick that set up the Colts' game-winning field goal in the championship game.

[9] Future NFL hall of famer Chuck Howley instead won that accolade, still the only player from a losing team in the Super Bowl to be named MVP.

[9] Curtis' 1975 season was cut short on November 12 when he opted for surgery to repair cartilage in his left knee, which he had injured in a preseason game in early September.

[15] Despite the objections of head coach Ted Marchibroda,[16] Curtis was left unprotected for the 1976 NFL Expansion Draft due to a personality conflict with general manager Joe Thomas.

[1] A self-described "loner" who preferred his own company or that of his family, Curtis had a 44-acre farm near Leesburg, Virginia, purchased with his winner’s share of the proceeds of Super Bowl III.

[23] Curtis struggled with memory loss late in life,[11] a condition associated with damage due to chronic traumatic encephalopathy (CTE), a neurodegenerative disease caused by repeated head injuries.

[11] Curtis is remembered for his role as a losing member of the Colts team in Super Bowl III, still regarded as one of the greatest upsets in NFL history.

"[24] He is also remembered more positively for his game-changing interception and return with little more than one minute left in Super Bowl V, setting up Colts kicker Jim O'Brien for the game-winning field goal.

[11] His friend and teammate, Colts center Bill Curry recalled of Curtis: "You really missed the thrill of getting to see a great NFL linebacker if you didn't see him play....