The former Barcelona forward has been strongly linked with a January move away from Stoke.
Karanka said: “I like to bring players who can play in different positions, so we will try.
“At the moment it is one signing, but if someone leaves it could depend.
“I know Bojan, because he was in the national team. He is a good player, he has played in AC Milan, Barcelona, Ajax, Rome, Stoke … so he is a good player.”