Nacional defender Juan Izquierdo, who collapsed on the pitch after suffering an irregular heartbeat last week, has died, his Uruguayan club said on Tuesday.

The 27-year-old had been undergoing medical treatment since collapsing during a CONMEBOL Libertadores game against Sao Paulo on Aug. 22 in Brazil.

"It is with the deepest sorrow and shock in our hearts that the Club Nacional announces the death of our beloved player Juan Izquierdo," Nacional wrote on X.

"We express our most sincere condolences to his family, friends, colleagues and loved ones. All of Nacional is in mourning for his irreparable loss."

Alejandro Dominguez, the president of CONMEBOL, also extended his condolences to Izquierdo's family and friends.

"South American football is in mourning," he added.

Sao Paulo said they were deeply saddened by the news, calling it a "sad day for football."

Izquierdo fell to the ground unconscious in the 84th minute of the match at the Morumbi stadium without coming into contact with another player.

He was taken off the pitch in an ambulance before being treated at the intensive care unit of the Albert Einstein Hospital.