[2] Born into a working-class family, Biondetti raced motorcycles before turning to automobiles where he had greater success.

Born in Buddusò, Sardinia, into a working-class family, Biondetti began his racing career in motorcycles in 1923 but in 1927 turned to automobiles.

Driving an Alfa Romeo 8C 2900b, Clemente Biondetti won the 1938 Mille Miglia for sports cars and at the Coppa Ciano finished second in the voiturette class then third in the main event.

Nevertheless, he dominated Italian endurance racing, driving to victory in the Mille Miglia for three straight years from 1947 through 1949 and the Targa Florio in 1948 and 1949.

Driving a self-built Ferrari-Jaguar hybrid car, engine problems forced him out of the race thus he failed to score any championship points.