Player A plays a Stadium card of a different name to a Stadium card currently in play directly from the hand to the discard pile, not being a part of any other game action (such as Ultra Ball, Professor Sycamore, etc.) Realizing this mistake, Player A picks the Stadium card back up, and attempts to take a different game action. Player B calls a judge. Both Player A and Player B agree upon this series of game actions taking place. Player B says that, because the Stadium card was played, albeit incorrectly, that the intent was for the Stadium card to be played, and that the new Stadium card should remain in play. With no other game actions having taken place so far, it is Player B's choice to allow or disallow the takeback of Player A's Stadium card. Player A says that, because the Stadium card was never played properly, that the playing of the Stadium card was a game-play error, and that the proper reversal would be for the Stadium card to be returned to the hand, as it cannot be played directly to the discard pile. As a result, the Stadium card never entered play, and Player B should not have the choice of if it remains in play or not. How should the improper play of this Stadium card be resolved? Would this be a minor or major game-play error?