The Greece Under-21 international, who spent last season on loan at Verona from the Grifone, has penned a contract with the Giallorossi until the summer of 2017
The Giallorossi revealed on their official website that they have agreed to pay the Rossoblu €2.5 million for a 50 per cent stake in the Greece Under-21 international, who spent last season on loan at Verona.
The versatile midfielder, who can also play at the back, has penned a five-year contract in the capital that will tie him to the club until June 30, 2017.
Tachtsidis joined Genoa from AEK Athens in 2010 but failed to make a single league appearance for the Grifone, and had also enjoyed loan spells at Chievo and Grosseto before being farmed out to Verona last year.
The Greek is the second new arrival at Trigoria in two days, following the signing of Leandro Castan from Corinthians on Wednesday.