Former Barcelona coach Tito Vilanova has died at the age of 45.
Vilanova underwent emergency surgery last night to treat gastric complications arising from the cancer he had been battling since 2011.
Earlier today, Villanova's condition was reported as stable by Catalan sports newspaper El Mundo Deportivo. However his condition deteriorated rapidly and he died this afternoon.
The news has been confirmed by FC Barcelona on their official website, after being broken by the Spanish press.
Vilanova, who was initially assistant to Pep Guardiola between 2008 and 2012, was named Barca coach when Guardiola resigned.
After taking charge for the 2012/13 season, during which Barca won the league title, the Catalan club announced that Vilanova would be stepping down due to a relapse of the cancer last summer.
Since then, Vilanova has kept fighting while the media respect his request for privacy.
According to Barca's official website, in the next few hours the Catalan club will create a space for condolences in one of the Camp Nou's grandstands.
Barcelona president Jose Maria Bartomeu said: "Tito Vilanova was a wonderful person, and will never be forgotten at FC Barcelona. Thank you for everything you taught us. Rest in peace."
Chelsea manager Jose Mourinho, who once poked Vilanova in the eye during an El Clasico encounter, reacted to the news by saying: "Tito Vilanova's passing is a sad day for football, for Barcelona and most importantly for his family and friends. On behalf of everybody at Chelsea Football Club I send my deepest condolences at this most difficult time."
Vilanova is regarded as a hero across Catalonia for his integrity and professional skill. Indeed his death has been mourned across all of Spain.
One fan responded to the news by posting on the Mundo Deportivo website: "I am a Real Madrid fan, but today I am with all the Barcelona fans to mourn a great loss to football."
Another wrote: "Such a sad day, not only for all the Barcelona family but also for the world of football, a man who didn't have problems with anyone and who no-one could dislike."
Many posters simply wrote 'Descanse en Paz'. the Spanish for 'Rest in Peace'.