The Mirror says Pochettino has targeted a £9.75m swoop for Cagliari's Astori, who was controversially left out of Italy's World Cup squad.
Cagliari sporting director Nicola Salerno confirmed: "At this moment, some big clubs in England and across Europe are following Davide. He has an international market because he is a very, very good defender - one of the best left-sided centre-backs in the game.
"Astori has one year remaining on contract, but could well leave Cagliari. If he does, though, it must be for big money."
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