On 23 November 1957, he also made his Serie A debut, in a 5–1 win against Sampdoria, soon becoming a permanent member of the starting eleven, and later serving as captain of the squad.

Following an argument with manager Edmondo Fabbri, he was left out of Italy's 1962 FIFA World Cup squad, which was eliminated in the first round of the tournament.

Along with Giuliano Sarti, Armando Picchi, Gianfranco Bedin, and Antonio Angelillo, he is one of the most successful Italian, Inter club players to have never been called up for a World Cup.

Despite his exclusion from the national side, in 1967 FIFA placed him in their All-Star team for an international friendly against Spain, in honour of goalkeeper Ricardo Zamora, winning the match 3–0.

[1][3] A predominantly left-footed player, Corso was noted for his consistency, intelligence, pace on the ball, and stamina as a winger, as well as being renowned for his accurate distribution, crossing ability, creativity, vision, and wide range of passing with his stronger foot, which made him an effective playmaker.

Although he was not particularly quick footed, he was gifted with tenacity and a good physique, as well as class, outstanding technical ability, close control, flair, and dribbling skills.