Cleber Santana, formerly of Atletico Madrid and Real Mallorca, is believed to have been among those killed in Tuesday's plane tragedy in Medellin.
The 35-year-old midfielder was on board the plane carrying the Chapecoense side that crashed in Colombia in the early hours of Tuesday morning, with early reports of 76 deaths amongst the 81 people on board.
Los Rojiblancos signed Santana from Brazilian side Santos for €8m in 2007 and he would make 37 appearances for the side over three years, and also spent a year on loan at Mallorca.
The plane was carrying players and staff of the Brazilian Serie A side to play in a Copa Sudamericana match in Medellin on Wednesday, but failed to reach its destination.
Former Villarreal player Alejandro Martinuccio did not travel with the squad due to injury, while former Pontevedra full-back Filipe Machado is also believed to be among the deceased.