The exhibition space for this installation is set as playground for a game played by two machines continuously throwing tennis balls to each other. Circulating through the space the visitors perceive the sound of the tennis balls hitting the floor, recalling the game atmosphere, and interact with the machines by interrupting the balls movement and by feeding them with the lost balls. Though the aim of every player is achieving preciseness, overcoming their own limits of resistance, is in fact in the error that the game becomes entertainment - the victory of one player depends of the failure of the other. Machines are optimized players, by being capable of endless repeated and geometric calculated movements, they go beyond the human limitations and surpass the proof of time. This game played between two machines and in between people is devoid of the failure or the victory - still the joy of the game is lived by the visitors since they can become part of the game, causing the error to happen. Machines are reliable and continuously precise through time - as Ellesse.