Marina Granovskaia, Chesea chief negotiator is currently working on a possible third transfer for the club.
The Blues are optimistic of convincing Gerson Santos da Silva, after successfully capturing Ajax winger Hakim Ziyech and agreed a deal with RB Leipzig for Timo Werner recently.
His club, Flamengo, are willing to sell the midfielder around £31 million, more than £20 million they paid to AS Roma in last July to re-sign him.
Gerson, 23 was pivotal in the win for Flamengo to their first Copa Libertadores title since 1981, wining Serie A title, Supercopa do Brasil, Recopa Sudamericana and played 102 minutes of the FIFA Club World Cup final extra-time defeat to Liverpool in December 2019.