Seriously? Thallen is the only person who actually understands the term 'pro' in this thread?

pro: abbreviation of professional.

professional: (of a person) engaged in a specified activity as one's main paid occupation rather than as a pastime.

Fun Fact: In Cuba, professional baseball existed from 1878 to 1961 (it was older than the American League). Then, the whole concept of professional baseball was abolished in Cuba. However, they still have an amateur national baseball league, which definitely brings up a huge amount of talent.