Atletico Madrid have announced that Christian Minchola, a 14-year-old forward who played for one of the club's youth teams, has died.
Minchola joined Atletico's academy in the 2013-14 season and had most recently played for their U14s in his sixth campaign at the club.
Club sources told ESPN that his death was not connected to coronavirus.
"We are saddened by the tragic news of the passing of our player and we mourn his loss deeply," Atletico Madrid president Enrique Cerezo said on Saturday.
"Atletico Madrid and all of the Atletico family are alongside Christian's family and friends in these moments of immense pain."
Rabia y dolor por tener que decir adiós a Christian Minchola. La vida es muy injusta. Orgulloso de que hayas vestido esta camiseta. Mucho ánimo a compañeros, familia y amigos. Descansa en paz. pic.twitter.com/yvvRuWG3bb— Koke Resurrección (@Koke6) March 28, 2020
"The feeling of powerlessness that situations like this generate is horrible," CEO Miguel Angel Gil said in a statement on the club's website.
"In the last few days people very close to me have died, some from coronavirus and others from other illnesses, and the feeling of not being able to say goodbye to them as they deserve, as in Christian's case, the feeling of such huge injustice, breaks your heart."
Club captain -- and academy product -- Koke tweeted: "Anger and pain at having to say goodbye to Christian Minchola. Life is so unfair. Proud that you wore this shirt."
Atletico Madrid have confirmed the flag outside the Wanda Metropolitano stadium will be flown at half mast as a tribute to Minchola and to all those Atletico fans who have died in recent weeks.