Mario Oscar Gerosa (born 27 April 1967 in Rosario, Argentina) is an Argentine-born Italian former rugby union player, coach and a current sports director.
He played as a wing.
Gerosa first team was Club Atlético del Rosario, where he won the Nacional de Clubes in 1987.
He would play there from 1984/85 to 1990/91.
He had 2 caps for Argentina in 1987, winning the South American Rugby Championship the same year.
He still scored 4 tries, 16 points on aggregate.
Gerosa moved to Piacenza Rugby Club in 1991/92, where he would stay until 1996/97.
He adopted Italian citizenship, being called for Italy, where he had 7 caps, from 1994 to 1995, scoring 4 tries, 20 points on aggregate.
He was called for the 1995 Rugby World Cup, playing two games and scoring a try in 31-25 win over Argentina, at 4 June 1995, in East London.
That would be his last cap for the national team.He returned to Argentina, playing for Rosario, from 1998/99 to 2009/10, when he finished his player career, aged 43 years old.
He later would be his team coach and sports director.