After the appointment of Quique Setien as new Barca coach, Mundo Deportivo says Spain international Ruiz will be on his radar. The pair worked together at Real Betis.
Barca are weighing up bringing Dani Olmo back to the club from Dinamo Zagreb, however an alternative could be Ruiz.
The midfielder is in second season in Naples and has been linked with Real Madrid after being left disappointed by the actions of president Aurelio de Laurentiis and his treatment of the players.
Setien revealed last summer: "Barcelona wanted to pay one million euros to take Fabian for their reserve team and I refused as we wanted him at Betis.
"When I arrived [from Las Palmas], I saw Fabian's potential and we decided to keep him.
"He needs to improve certain things, but he has an incredible ability to learn and he has a wide development margin.
"[Napoli] paid 30 million euros for him and if he had continued [at Betis] I have no doubt that they could have earned 60m euros from his transfer at the moment."