The Camp Nou outfit are likely to stay without Dani Alves in the summer, whilst Martin Montoya has yet to sign an extension to his contract that expires in June.
As a result, they are in the market for a new right-sided defender, and Sport understands Porto full-back Danilo is one of their primary targets.
The Brazilian joined the Dragons in January 2012 in a big money move from Santos, and he has quickly justified his price tag.
Danilo went on to make 56 league appearances for Porto, scoring 4 goals, while participating in 17 European matches.
He has seen his name linked with a number of high-profile clubs in the past, and it looks as though the Dragons face a real battle on their hands in an attempt to keep hold of him beyond the current season.