Probably a soldier from a metope.
One of a large number of sculptural fragments from the temple, of which nothing else survives. Behind the figure’s left shoulder is a fragment of a shield, and we can also see the hand of his opponent, probably an Amazon. According to Pliny the gold and ivory cult statue of Hera in the temple was made by Polykleitos, a native of Argos
Athens, National Museum 1561-1583
Waldstein: The Argive Heraeum I, pl. XXXIV
Lippold: Griechische Plastik, pl. 74.3
Kähler: Das Griechische Metopenbild (1949), 110, no.91, pl. 91
Found on site of the Heraeum in the Argive Plain