Marcelo had his contract ripped up over the weekend after a blow-up with Flu coach Mario Menezes.
Taking to social media, Marcelo stated on Monday evening: "I have had a wonderful time at this club. Almost two years ago I decided to return, motivated by the sentimental bond with the team.
"I have participated in unforgettable moments such as the victory of the first Copa Libertadores in the club's history. My name will remain immortalized at the Marcelo Vieira stadium, where our boys train every day.
"I want to thank my wife and children for always being by my side and for all the sacrifices they have made for me. I am proud of what I have achieved and I thank everyone who has made this adventure unique, especially the president, the staff and my teammates. I also thank the fans for their support. I will always carry Fluminense in my heart.
"The truth, like the Sun, will always come out."