Less than two months after he was unveiled as Home United coach on July 2, Raddy Avramovic has stepped down to return to his native Serbia to seek medical treatment.
The 69-year-old is understood to have been diagnosed with second-stage lung cancer.
Home United general manager Badri Ghent said yesterday: "We are shocked by this unexpected news and everyone at the club wishes him a speedy recovery.
"We are honoured that someone of his stature has led the club, despite the short tenure.
"He has definitely made a positive impact on everyone at Home United during his time with us."
Avramovic took over after the Protectors parted ways with his predecessor Saswadimata Dasuki in April.
Home United were sixth out of nine teams in the Singapore Premier League and Avramovic engineered four wins and a draw in eight games to help them improve to fifth.
Avramovic is Singapore's most successful national coach, leading the Lions to three Asean Football Federation (AFF) titles in 2004, 2007 and 2012 during his tenure from 2003 to 2012.
Home announced that assistant coach Noh Rahman will take over on an interim basis while they search for a replacement.
Noh said: "Raddy has made his mark with the national team and we were confident he would with Home United too.
"We are sad to hear the news but some things, such as health, are more important than football.
"Knowing the fighter that he is, we believe he will make a full and speedy recovery and we hope to work with him again.
"We want to carry on his good work for the rest of the season and end strong to thank and encourage him."