Complex sentence: In the list of "Greatest Sports Performances" (by individual athletes), the horse was the only nonhuman on the list, with his run at Belmont ranking second behind Wilt Chamberlain's 100-point game.
Split into simpler sentences: In the list of "Greatest Sports Performances" (by individual athletes). The horse was the only nonhuman on the list, with his run at Belmont ranking second behind Wilt Chamberlain's 100-point game.