Mark Gonzalez is in recovery in a hospital, according to his wife.
The former Liverpool player and Chile international has suffered a heart attack.
And Liverpool tweeted their concern over his condition.
The 36-year-old joined the Merseyside club in 2005 when Rafa Benitez decided to sign him from Albacete for £2.25 million.
Before retiring last year, the Chilean made 25 league appearances for Liverpool, as well as appearances for Real Sociedad, Real Betis, and CSKA Moscow, among others.