Brazil superstar Neymar departed Camp Nou for a world-record move to Paris Saint-Germain ahead of the 2017-18 season but has consistently been linked with a move back to Barca.
Despite regular speculation ahead of the 2019-20 campaign, Neymar remained in the French capital and has scored 18 goals in 22 appearances across all competitions this term.
Neymar is once again being tipped to join Barca, though it was said at the time he left the club in part to try and escape the shadow of superstar team-mate and now six-time Ballon d'Or winner Messi.
But Mazinho feels the 28-year-old is ready to come back and is capable of taking on Messi's mantle as Barca's talisman.
Speaking to Radio Marca, he said: "[Barcelona] would be delighted if he can return tomorrow.
"He is Messi's natural replacement. There is no other to replace Messi."
Mazinho's son Thiago Alcantara is part of a Bayern Munich side who returned to training this week amid the coronavirus pandemic.
The Bundesliga champions trained in small groups without contact and Mazinho, who was part of the 1994 World Cup-winning Brazil team, said he trusts the club have taken appropriate measures.
"[Playing football amid the coronavirus outbreak] is worrying because it is a complicated situation that we are all experiencing," he added.
"In Germany they are progressing in that sense, with group training.
"You have to be very careful with all this. If Bayern do it, they do it because there is no risk and they are providing security to all their footballers.
"My son must work and be as prudent as possible."