The Blue Sox have been a member of the New England Collegiate Baseball League (NECBL) since 2008, playing home games at MacKenzie Stadium in Holyoke. The NECBL is one of three collegiate leagues funded in part by Major League Baseball and is comprised of 12 teams throughout all 6 New England States.

Blue Sox and NECBL players come from the top college programs across the country, some of whom are drafted into Major League Baseball. In all, twenty-nine of the thirty teams in Major League Baseball have had NECBL alums on their rosters. Notable recent alums include Stephen Strasburg, Mark Appel, Andrew Ethier, Andrew Bailey and Joe Nathan.