The Sea Dogs became part of the Red Sox system for the 2003 season; previously they were affiliated with the Florida Marlins. The change in affiliation brought success in the 2005 and 2006 seasons as the Sea Dogs went to the Eastern League championship series both years. They won their first-ever title on September 17, 2006, defeating the Akron Aeros 8-5 in a rematch of the series from the previous year. It was the first double-A championship for a Red Sox farm team since 1983 when they were based in New Britain, Connecticut.