Mario Negri played football at the club level as a youth, from 1903-16, and also played tennis, pelota, golf, swimming, and water polo recreationally. In sports administration he was President of the Argentine Swimming Federation from 1929-51 and 1956-61. He was a member of the Executive Board and Vice-President of FINA (Fédération Internationale de Natation Amateur) from 1952-56. He also served as Vice-President of the International Pelota Federation from 1947-60. He became an IOC Member in 1960, staying on the Committee until he turned 85, in 1974.