Robert Waseige, the former football player and manager - who notably trained the Red Devils between 1999 and 2002 - died on Wednesday aged 79, RTBF announced.
He was taken to hospital on Thursday (CHR de la Citadelle in Liège), where he was treated for heart failure and kidney problems.
He underwent a heart-bypass operation in 2001 and has since had regular checkups. Waseige leaves a widow, Aline, and three boys Frédéric, William and Thierry.
The Brussels Times