Former Liverpool manager Gerard Houllier has died at the age of 73
The Frenchman, who also managed Paris Saint-Germain and Lyon, had a long history of medical issues, most notably a heart problem, but the cause of his death remains unknown.
French radio station RMC sport and sports newspaper L'Equipe have reported Houllier died after having a heart operation in Paris.
A fan favourite at Anfield, Houllier suffered a life-threatening vascular problem during a Premier League match against Leeds in 2001.
He was quickly rushed to hospital and later needed 11 hours of open-heart surgery after suffering a heart conditions known as 'dissection of the aorta'.
Houllier arrived at Liverpool in the summer of 1998, initially as joint-manager with Roy Evans before taking sole charge just four months later.
He oversaw a major rebuilding of the first-team squad, signing the likes of Sami Hyypia, Dietmar Hamann and Vladimir Spicer, and changed the tactical philosophy to make them a force once again.
Houllier's methods quickly brought rewards as the Reds won a unique treble in 2000-01, as well as a third-place finish in the Champions League.
In 2002 Houllier was awarded the Legion d'Honneur - one of France's top civil awards.
He was largely credited with laying the foundations for the national team's dominance of world football following the establishment of the French academy system.
Players that came through the system helped France win the World Cup in 1998 and the European Championship in 2000.
And Houllier, a former English teacher, was also seconds from taking France to the 1994 World Cup before losing to Bulgaria at the Parc des Princes.