Betis are keen to sign the Brazil international, but Barca will only release him for loan if they agree to an obligatory permanent option.
Rafina's father, Mazinho, told El Desmarque: "Betis is very interested and is an important option for the boy that we are evaluating. He has spoken with the teammates he knows there and they have spoken very well about Betis.
"(Betis sports chief Lorenzo) Serra Ferrer wants him.
"If Betis wants Rafinha, they already know what they have to do."