Rivaldo believes Real Madrid captain Sergio Ramos would be a good signing for bitter LaLiga rivals Barcelona.

Ramos is out of contract at the end of the season and the superstar defender is yet to agree a new contract with the LaLiga champions.

The 34-year-old Spain skipper has been linked to the likes of Manchester United, Manchester City and Juventus.

Rivaldo, who won two LaLiga titles among other honours during his time with Barca, backed Ramos for a controversial move to Camp Nou.

"A player has to be professional, and if you have good offers, I don't think it's okay to hear them," former Brazil international Rivaldo told Betfair.

"Of course, Sergio Ramos would be a good signing for Barcelona. It would be historic and it would be controversial because of Sergio Ramos' history with Real Madrid."

Ramos has called Madrid home since joining from Sevilla in 2005, winning five LaLiga trophies, four Champions League titles, as many Club World Cup crowns and three UEFA Super Cup medals among 22 major honours at the Santiago Bernabeu.

There is also speculation over Lionel Messi's future, with the Barca skipper tipped to leave the Catalan powerhouse on a free transfer at season's end.

Messi – a record six-time Ballon d'Or winner – has been heavily linked with Ligue 1 champions Paris Saint-Germain and Premier League leaders City.

"If I were [PSG head coach Mauricio] Pochettino, I would tell the owner of PSG that we'd better stay the way we are before bringing in Messi," Rivaldo said. "I like Messi, but [Kylian] Mbappe is at home and there would also be everyone in their team.

"It is difficult to talk about a change from Messi to Mbappe, because football is money and if Messi goes to PSG, he will have many economic benefits. But of course, Messi is already more than 30 years old and in PSG there is already Mbappe with 22 years. It is difficult.

"PSG, I repeat, I think they do not need any signings because they have a great team… but football is also a business."