The defender, 22, has joined the Nerazzurri as part of the deal that saw Gianluca Caprari move the other way
Inter have completed the signing of Sampdoria star Milan Skriniar on a five-year deal.
The Nerazzurri have reportedly paid close to €20 million for the 22-year-old after allowing forward Gianluca Caprari to move the other way last month as part of the deal.
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Skriniar is Inter's first major signing of the transfer window following the earlier arrivals of youngsters Nicolo Zaniolo and Jens Odgaard and goalkeeper Daniele Padelli.
The defender made 35 appearances for Samp in 2016-17, becoming the youngest defender to do so in a single Serie A season.
The Slovakia international started all three of his side's matches at the European Under-21 Championship in Poland and was included in UEFA's Team of the Tournament.