Abstract: An amusement or gaming machine has a gamble wheel assembly which comprises a gamble wheel rotatably mounted in a machine cabinet about an axis inclined at an acute angle or at a right angle to the vertical, the wheel being formed with a plurality of circumferentially arranged ball carrying pockets, so arranged that when a ball is in a pocket at least part of the ball is visible from the front side of the wheel, a fixed part-annular ball retainer extending circumferentially about the wheel axis adjacent to the pockets to retain captive a ball that has been captured in a pocket in a ball capture region of the rotational path of the pockets, a ball supply unit for delivering a ball directly or indirectly to the ball capture region for capture in a pocket. Controllable release means is provided for releasing a captured ball from the pockets to be received in a ball outlet.