Fluminense named Vanderlei Luxemburgo as its new manager on Wednesday to replace Abel Braga, who was relieved of his duties earlier this week.
Fluminense won the Brazilian title last season, but a run of five successive defeats has left the club languishing near the relegation places, costing Braga his job.
Luxemburgo has managed at Real Madrid and was most recently in charge of Gremio before being fired earlier this year.
"This team lost only three matches when it won the 2012 Brazilian title," Luxemburgo said. "We have to restore that type of confidence to try to put Fluminense back atop of the standings, which is where it belongs."
Luxemburgo joins the defending champions on a contract that runs through the remainder of the season.