Flamengo, facing Libertadores Cup exit at the group stage, sidestepped angry fans' plans to pelt them with eggs on Thursday's arrival at Rio de Janeiro airport from Ecuador where they lost 3-2 to Emelec.
The fans did not even get a glimpse of Ronaldinho's team and Joel Santana's coaching staff who were ushered away through a secret exit having dropped to the bottom of Group Two with one match to play, Brazilian media network Globo reported.
"It's difficult to explain the inexplicable," Santana was quoted as saying by Gazeta Esportiva in Guayaquil after the defeat.
Santana suggested Flamengo did not know how to manage their lead, saying: "We conceded the (last) goal knowing what was going to happen. I think we're lacking maturity.
"You take the lead once, then again, and in the final 12 minutes you hand over the game. It's difficult (to explain), we've got to talk to the players and the technical commission because something's wrong. We have to rethink some concepts," he said.
To qualify for the knockout phase, Flamengo need to beat Argentine group leaders Lanus in Rio next week and hope for a draw in Asuncion where second-placed Olimpia of Paraguay host Emelec in a match the Ecuadoreans must win if they are to go through.