Goran Bunjevcevic, who made 51 appearances for Tottenham during a five-year spell at White Hart Lane, has died at the age of 45.
Bunjevcevic's former club Red Star Belgrade announced the news on their official website, saying he had suffered an aneurysm in May.
The statement read: "With sadness we report that Goran Bunjevcevic, former Crvena zvezda captain and director of football, has passed away on 28 June 2018. He was 45 years old.
"Goran fought bravely for over a month after suffering an aneurysm on 20 May this year, but has today tragically lost the battle."
Bunjevcevic left Tottenham in 2006 and spent a short period with Den Haag in Holland before retiring and eventually taking up a new position as sporting director of the Serbian Football Association.
Tottenham posted on Twitter: "We are deeply saddened to hear of the passing of our former player Goran Bunjevcevic. The thoughts of everyone at the Club are with his friends and family at this extremely difficult time."
Bunjevcevic was a popular figure in Serbian football, having captained Red Star Belgrade to a league title in 2000 and made 16 appearances for the Yugoslavia national team.
We are deeply saddened to hear of the passing of our former player Goran Bunjevčević. The thoughts of everyone at the Club are with his friends and family at this extremely difficult time. pic.twitter.com/UryBkqz6as— Tottenham Hotspur (@SpursOfficial) June 28, 2018
After Serbia's opening World Cup win over Costa Rica two weeks ago, defender Aleksandar Kolarov dedicated his match-winning free-kick to Bunjevcevic.
Kolarov told reporters: "We dedicate this win to our director, and we want him to know that we are all supporting him.
"He's had some health problems. We want to relay this message to him and his family that we are 100% behind him."