Argentine midfielder Juan Roman Riquelme would be more than welcome at Fluminense, according to Deco.
The former Villarreal playmaker called time on his second spell at Boca Juniors in the off-season, having spent a total of 10 years playing at the club.
He has since been linked with a host of clubs, including the Brazilian champions, and Deco insists he would not be threatened by extra competition for his playmaking spot.
"I do not know if he will be recruited, it is the directors who manage that part but if this is the case, he will be welcome here, without doubt," he told Globoesporte.
"I do not see any problem. Players adapt easily to quality players."
Having won the Brazil Serie A in 2012, Deco is now setting his sights on continental glory by winning the Copa Libertadores.
"The Libertadores is a dream, not only of the fans but also the players," he said.
"I have never won this competition and I'm preparing for that, but football is not an exact science, it's not just train and win.
"There are other teams that are also prepared and want to win as much as us."