At the end of the 1998 season, the FGBA joined with two other MBA member associations, the Cawthra Baseball Association ("Cawthra") and the Bloor Baseball Association ("Bloor"), in founding the Mississauga Majors Baseball Association (the "Majors").  The FGBA had the right to appoint one of the five members of the Majors' Board of Governors.

Up until the Majors was created, both Cawthra and Bloor had administered separate 'AAA', or "Rep", baseball programs, both entering teams in all or most of the province-wide 'AAA'  Series managed by the Central Ontario Baseball Association.  The FGBA drew on too small  a pool of playing and coaching talent to be able to support its own 'AAA' program, but referred its most advanced players and coaches to either Cawthra or Bloor for 'AAA' try-outs.   The formation of the Majors combined the 'AAA' programs of Cawthra and Bloor, drawing one team for each Series from the combined talent pools of Cawthra, Bloor and the FGBA.  At the end of the 2004 season, Cawthra and Bloor merged to form the Mississauga Majors Baseball Association.  The FGBA continues to refer players and coaches to their 'AAA' program.

The 'AAA' Program offered by the Majors is aimed at those players at each Level that have demonstrated the most highly developed skills.  By participating as a founding member of the 'AAA' Majors, the FGBA has been able to provide access by its most talented players to a higher level of competition, and so to contribute to the improvement of the baseball programs offered at all levels of play in central and eastern Mississauga.