Toledo's Tunisian forward Lassad Nouioui, who has also played for Celtic and Deportivo La Coruna, has been taken to hospital after collapsing on the pitch during a training session on Saturday, the Spanish third division side said.
"The player fell unconscious on the pitch after suffering ventricular fibrilation and after receiving cardiopulmonary resuscitation he was taken to hospital in an ambulance," said a statement from Toledo.
"The quick reaction of his team mates and the emergency services were key to stabilising the player. Lassad, with a reserved prognosis, will remain under observation for the next 48 hours and will continue to undergo tests.
Lassad, 32, who has two caps for Tunisia, played 107 games for Deportivo in La Liga and the Segunda Division between 2008 and 2012. He featured 17 times for Celtic in the 2012/13 season, winning the Scottish Premier League and Scottish Cup.
"After speaking to the Spanish Football Federation and Real Madrid Castilla, the club has asked for Sunday's game against Castilla to be postponed. CD Toledo would like to send all the strength in the world to Lassad," the club added.
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