Eine "Homerische Gruppe" in den Horti Sallustiani?

A sculptural fragment cemented in the wall of the large loggia of the Swiss Institute in Rome was presumably found in the region of the horti Sallustiani. It comes from a statue of unusual type. The arm is strongly bent at the elbow and wrist; most likely, it belonged to a combatant unsheating his sword. In style and subject, the sculpture can be connected with the so-called "Homeric Groups" that were very popular in the Late Hellenistic period and often used to decorate Roman villas. Pompeian frescos show Achilles fighting Agamemnon in a similar stance; on sarcophagi we find a related figure in Diomedes discovering Achilles on Skyros. It is unclear whether the fragment belongs to an original, Late Hellenistic creation or to a Roman copy.