Roma have completed the signing of Argentina attacking midfielder Javier Pastore from Paris St-Germain for 24.7 million euros (£21.8m).
The 29-year-old, a reported target for West Ham, has signed a five-year deal.
PSG need to make 60m euros (£52.9m) from player sales by the end of June to comply with financial fair play rules.
Pastore joined PSG in 2011 for a reported £37m and played more than 250 games, winning the domestic treble on three occasions.
"The signing of Javier makes me very happy because we are talking about the sort of player who can excite the fans who he plays for," said Roma sporting director Monchi.
"In my career I have signed a lot of players, but Javier might just be the one with the most talent."
Pastore is Roma's eighth signing of the summer and he joins on the same day the club announced deals for defender Davide Santon and midfielder Nicolo Zaniolo.
Santon (9.5m euros) and Zaniolo (4.5m euros) arrived from Inter Milan, while Belgium midfielder Radja Nainggolan went the other way.
Roma also completed the signing of winger Justin Kluivert from Ajax on Friday.