Foot Mercato says that the Italy International is being viewed by both Premier League Giants.
Retegui only moved to Atalanta from Genoa in August and enjoyed an excellent first season with La Dea.
The striker has already scored 20 goals this season in the Serie A – and became the first player to do this at this stage of the season.
Contact with Retegui's management was already made by Arsenal and United prior to plans for a relocation this summer.
Retegui was born and bred Argentin's, but qualifies for Italy through his parents and was first covered by Italy when he played for Tigres in Argentina.
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