The bottom right panel illustrates the final moments of a well known musical contest between Marsyas the silenus, a virtuoso flute player, and Apollo, god of the arts, patron of the Muses and a remarkable player of the lyre. After the unsuccessful bid to win the contest, Marsyas was condemned to death by Apollo for daring to challenge the god. Apollo is seated upon a rock wearing the splendid attire of a kitharodos (kithara player), his head surrounded by a halo and adorned with a wreath of laurel leaves, embellished with a fillet of white and red beads. He is leaning upon his favorite instrument, the lyre, and his right hand, pointed at Marsyas, holds a golden plectrum used for plucking the strings. He is accompanied by a woman, identified by an inscription as Plane, who can be understood as a personification of the “errant mind”, that of Marsyas whose pride mislead him into provoking the god.

Two Scythians clad in Phrygian caps and short tunics execute the verdict. They lead Marsyas, who is dressed in a panther’s skin, towards a tree where he will be flayed alive. Stricken by horror and grief, the silenus looks pleadingly at Apollo. Olympus, his young pupil, implores the god to be merciful. Marsyas’ double flute rests on the ground by Apollo’s feet. The scene is full of expression; the artist has managed to differentiate the psychological attitudes of the participants. Haughty and severe, the face of the god contrasts with those of the self-assured executioners.