A mechanical shoeing and, more specifically, a shoe which is intended to be mounted to the hoof of a sport horse that comprises: a front central part (3) or toe piece; two side branches (4 and 5) or quarters which extend freely from each side of the front central part, rear end portions (6 and 7) thereof forming heels; and holes (8, 9, 10, 11, and 12, 13, 14, 15) or nail holes which are defined in the side branches (4 and 5) in order to receive nails for fixing to the hoof (2). Moreover, in plan view, the inner hoof-facing surface (2) of each of the side branches (4 and 5) comprises zones (D and E) which belong to the rear end portions (6, 7) or heels and which are flared and, as well, are wider than the side branches (4, 5). In plan view, the inner face of each of the side branches (4 and 5) of the shoe also comprise a zone (A, B) which has a simple curved inner profile and which is narrowed such as to be narrower than zone C of the front central part (3) or toe piece.