John Desmond Sinnott (born April 18, 1958) is an Irish former professional American football offensive tackle in the National Football League (NFL). He was selected by the St. Louis Cardinals in the third round of the 1980 NFL draft. Sinnott played college football at Brown. He attended Dedham High School and was an inaugural member of the Dedham High School Athletic Hall of Fame.
https://www.pro-football-reference.com/players/S/SinnJo20.htm