Rainville, who performed for New Britain in the Double-A, Eastern League for portions of the 2008 and 2009 seasons, led his high school team to the Rhode Island State Championship in 2003. He was a perfect 8-0 that season with a 0.00 ERA; he was subsequently named the state's Gatorade Player of the Year.
In 2005, the affable hurler was 8-2 for Beloit in the Single-A, Midwest League and was named a League All-Star.
In 2006, Jay spent the entire season on the Disabled List with a nerve injury in his right shoulder. He returned to active status in 2007 and won 9 games for Ft. Myers in the Florida State League.
In 2008, Rainville was promoted to New Britain where he again won 9 games with a 5.78 ERA in 24 Double-A appearances. He voluntarily concluded his career with the Rock Cats after making nineteen 2009 appearances – 13 of which were starts – and compiling a 3-3 record and 5.56 ERA. His final appearance in a New Britain uniform came on August 8th in Akron, OH when he tossed 1 inning of relief against the Aeros. He ends his 2009 Season with a record of 3-1 at New Britain Stadium where, because of his local roots and outgoing personality, he was always a fan favorite.
The Rock Cats thanked Jay Rainville for his diligent service and wished him the very best in the future.