LISBON, May 2 (Xinhua) -- Porto goalkeeper Iker Casillas had a heart attack but is out of danger, Porto said Wednesday.

The Portuguese football club said Casillas suffered a sudden heart attack after training during a practice session and was then rushed to hospital for emergency treatment. It is also reported that Casillas's "heart condition has been resolved" and he was out of danger after receiving surgery.

The 37-year-old Spaniard extended his contract until the end of the 2019-2020 season in March with Porto, which he joined in 2015. Before, he played 16 seasons for Real Madrid as a key goalkeeper, helping win five Spanish league titles and three Champions League trophies.

In this season, Casillas' performance was also impressive. Porto currently rank second in the Portuguese Primeira Liga, two points behind Benfica. This accident could cast a shadow over its pursuit to retain the title, with only three games to play this season.

It still remains uncertain whether the veteran goalkeeper can continue his career, but Casillas is sure to miss all games this season.