"Tragedy struck Espanyol and the family of Dani Jarque this evening. The player died from a cardiac arrest," said a club statement.
"The doctor carried out CPR on the player and used a defibrillator, which showed that the arrest was non-responsive.
"RCD Espanyol, broken with pain, wish to put themselves at the absolute disposition of the family of our captain Dani Jarque, to whom go our warmest thoughts."
"We are returning to Barcelona on Sunday but we can't come back with the coffin because they have to do an autopsy to confirm the cause of death," added club director German de la Cruz.
"The players are destroyed. One minute he was there with them, and the next he's gone. It's terrible."
"We are filled with extreme dismay at this tragic event which we deeply regret," he told the Barcelona club website.
"We are all in mourning. I want to send, on behalf of FC Barcelona, our deepest sympathies to RCD Espanyol for the painful loss of their captain Dani Jarque, and to his family."
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