In ancient mythology, Hercules and Achelous were rival suitors of the nymph Deianeira. As they wrestled for her hand, Achelous transformed himself into a bull, but Hercules defeated him by tearing off one of his horns. Aspertini was one of the great eccentrics of sixteenth-century Italian art, and in this drawing any pretence of anatomical accuracy or classical proportion is sacrificed to expressive force. A technically similar drawing from the legend of Hercules is in the Uffizi, Florence, so this may have been part of a series.