Palace are sweating over the future of Zaha whose current contract will expire at the end of the month.
He has an offer on his table from Qatar, while Atletico Madrid are also interested in signing the 30-year-old winger.
Crystal Palace have offered him a new deal worth £200,000 per week and want an answer from the player by the end of June.
The club are already looking at potential replacements and the 19-year-old Franca has emerged as a distinct possibility.
The teenager is considered a big talent in Brazil and has scored nine goals in 52 senior appearances for Flamengo.
Arsenal are also interested in signing him and are believed to be keen to take him to England this summer.
Crystal Palace are seriously considering signing him if Zaha leaves, with sporting director Doug Freedman leading the charge.
The Eagles deal-maker has been in Brazil a few times to personally watch Franca play as part of the club’s scouting process.
Should Zaha move on this summer, Crystal Palace are likely to pursue the teenager’s signature this summer.
