Brazil international Hernanes completed a move from Inter Milan to Juventus just before the transfer deadline on Monday evening.
The former Sao Paulo midfielder arrived in Turin for a medical and completed the paperwork on a three-year deal just before the window closed at 11 p.m.
- JuventusFC (@juventusfcen) August 31, 2015
The Bianconeri had already agreed terms with Inter on a transfer worth €11 million.
A statement published on Juventus' website confirmed the amount paid to Inter could increase by €2million "should certain sporting targets stipulated in the agreement be achieved before June 30, 2018."
The former Lazio attacking midfielder became a Juve target at the weekend, after an attempt to sign Julian Draxler from Schalke failed.
The 30-year-old forged his reputation as one of the most accurate passers in Serie A during his four years with Lazio. He left the capital in January 2014 to sign a four-and-a-half year contract with Inter, for whom he would make 50 league appearances, scoring seven goals.
His place in the Inter squad is set to be taken by Adem Ljajic, who became a late target after attempts to sign Eder from Sampdoria broke down. The Roma forward was also joined by Galatasaray's Felipe Melo.
There was one more signing for Juventus at the deadline as midfielder Mario Lemina joined from Marseille.
- JuventusFC (@juventusfc) August 31, 2015
The highly rated midfielder joined the Bianconeri on a season-long loan with an obligatory option to buy for €11 million.
Juve have made their worst ever start to a top-flight campaign and critics have pointed to a lack of both bite and creativity in midfield following the summer departures of Andrea Pirlo and Arturo Vidal, to New York City FC and Bayern Munich respectively.