In February, 1963, an unusual discovery was made at La Ventilla, less than a mile from the “Ciudadela” in Teotihuacán, Mexico. This find is a composite or sectional stela made up of four superimposed elements that fit into each other by means of stems and orifices. All elements are different in form and are, from top to bottom, discoidal, globular, conical, and cylindrical, the last fitting into a platform base. This piece is unique in Mesoamerican archaeology and seems to have no significant parallels elsewhere. This stela was carved during the Classic period of Teotihuacán. Its function has been clarified through comparison with mural paintings of the Tlalocan in Tepantitla, Teotihuacán, where a ball-game scene is portrayed, and at each end is a stela that is almost identical with that of La Ventilla. It seems evident that the La Ventilla monument is a ball-court stela-marker.