Primo Carnera was an extremely well-built man who possessed great strength and was quite mobile for such a large man; however, his chin was vulnerable to the type of power punch that the top heavyweight fighters were able to deliver. His punching was hindered somewhat by his heavy muscles but nevertheless he scored many knockouts due to his considerable strength and power. Primo began fighting in Europe and then migrated to the United States. Many observers felt that many of his wins were "fixed" due to some connections held by those managing him. This shadow of doubt has caused boxing people to question his true ability as a fighter. During his career, Carnera won the Heavyweight Championship of the World and defeated such men as Jack Sharkey, Tommy Loughran, George Godfrey, W.L. "Young" Stribling, Franz Diener, Paulino Uzcudun, Pierre Charles, Ernie Schaaf, King Levinsky, Vittorio Campolo, George Cook and Jose Santa.