Collection of three Oakland Athletics team-signed baseballs, each dating from a different World Championship season. 1) 1972 World Champions Reunion Ball. Twelve blue-ink signatures (averaging 8/10) on an ONL (Giamatti) ball, including Finley (team owner, sweet spot), Fingers, Odom, Alou, and Tenace. EX-MT, with light age toning. 2) 1974 World Champions. Twenty-nine blue-ink signatures (averaging 8/10) on an Oakland A's souvenir ball, including R. Jackson (on ball label), Hunter, Fingers, Blue, Dark (Mgr., sweet spot), Campaneris, Rudi, North, and Odom. EX. 1989 World Champions. Twenty-eight ink signatures (various colors; averaging 8/10) on an Oakland A's souvenir ball, including McGwire, Canseco, LaRussa (Mgr., sweet spot), Eckersley, Parker (on ball label), Lansford, and Steinbach. "1989 World Series" is written on the ball label in blue ink. NM-MT.