Albion have confirmed the signing of Valentin Barco from Boca Juniors.
He arrives on a four-and-a-half-year contract until June 2028.
Barco, 19, can play at left-back or further forward and is widely regarded as a hugely exciting talent.
He made 35 first team appearances for Boca and delayed his expected exit from the Buenos Aires giants to help them attempt to win the Copa Libertadores.
Barco is currently away with Argentina under-23s at the CONMEBOL qualifying tournament for the Olympics.
Speaking to The Argus, Argentinean top-flight star Francis Mac Allister - brother of Alexis and a former team-mate of Facundo Buonanotte at Rosario Central - likened Barco's style to that of Arsenal's Oleksandr Zinchenko.
Mac Allister, who keeps close tabs on Albion, said Barco looks a perfect fit for Roberto De Zerbi's way of playing.
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