Rostagni, a native of Drap in southern France, honed his football skills at Cavigal de Nice before joining AS Monaco as a defender in 1966. He made 124 appearances for the club until 1970 and earned his first cap for the French national team in 1969.
He later played for Bordeaux, featuring in 57 matches, then Paris Saint-Germain (32 games), and Paris FC (58 games). Rostagni concluded his professional career between 1973 and 1975 with his beloved club, OGC Nice, where he played 28 matches. He accumulated 25 caps for the national team, known as Les Bleus, between 1969 and 1973.
After hanging up his boots, he transitioned into coaching at Peymeinade. He remained deeply connected to his home region and, according to the newspaper Nice-Matin, will be laid to rest in his hometown of Drap.