Ronald J. Belisario is a professional baseball player from Venezuela who plays as a pitcher. In 1999, Belisario made his appearance on the world stage after declaring for the 1999 MLB Amateur Draft. However, he went undrafted and at the end of it all, Belisario was signed by the Florida Marlins as a 16-year old free agent. Belisario began his career playing in the Rookie League for the Gulf Coast Marlins in 2001. This came after a stint in the Venezuelan Summer League in 2000.
In 2002, he played in the A-League for the Kane County Cougars before moving up to the Jupiter Hammerheads, in 2003, for the Advanced A-League. Injury struck his stint in the Advanced A-League and upon returning to action, Belisario was sent back to the Rookie League to restart his climb.
During 2004, was forced to end his season early after undergoing a Tommy John Surgery on his right elbow. Missing 2005 for the recommended recovery period, Belisario was suspended in 2006 however the reason for his year-long suspension was not revealed by the team.
Belisario finally returned to baseball in 2007, although this time after signing with the Pittsburgh Pirates, and played for the Lynchburg Hillcats in the Advanced A-League. Midway through the season, despite a 0-3 record and a 4.46 ERA, Belisario was promoted to the AA-League to play for the Altoona Curves.
Belisario began 2008 with the Curve and 38 games and a 4-4 record later, was traded out to the Los Angeles Dodgers. The Dodgers decided to start Belisario in the Advanced A-League and he was sent to play for the Inland Empire 66ers along with an invite for Spring Training.