Although he represented several Italian clubs throughout his career, he is mostly remembered for his successful stint with Juventus, where he won three Serie A titles.

At international level, he represented the Italy national football team at the 1954 FIFA World Cup.

[3] He was brought in as a replacement for Lucidio Sentimenti (IV), and made 246 appearances for the Turin club, winning the Scudetto on three occasions: in 1950, 1952 and 1958.

He made his debut at the 1954 FIFA World Cup, in the 4–1 first round play-off defeat of Switzerland.

[1][3][6] Regarded as one of the best and most consistent Italian shot-stoppers of his generation,[7] and as one of Juventus's greatest goalkeepers of all-time, Viola was an efficient and reliable keeper, who was known in particular for his composure in goal, although he also had the ability to produce acrobatic saves when necessary due to his agility and athleticism.