According to Portuguese newspaper O Jogo, Porto president confirms Casillas will retire due to heart attack.
On the front page of the Portuguese newspaper O Jogo, it claims that Porto president Jorge Nuno Pinto da Costa says Casillas will retire but he will stay working in management at Porto.
Casillas made 31 league appearances for FC Porto this season. He had signed a new contract with the Portuguese giants that runs until June 2020, with an optional second year.
Porto team doctor Nelson Pulga said at the time he expected Casillas to make a full recovery but claimed it was too early to make an assessment on whether the veteran goalkeeper would return to play.
Casillas joined Porto in the summer of 2015 on a free transfer after 16 years at Real Madrid.