Actor Sylvester Stallone was knocked unconscious while filming a scene for the sixth "Rocky" movie "Rocky Balboa" and needed urgent medical attention.

According to hollywood.com, Stallone suffered an injury while shooting the film scenes in the ring. He fell unconscious but the film crew failed to raise the alarm believing he was still acting.

Stallone's mother Jackie said: "At first everyone thought Sylvester was acting when he fell to the floor, but it was serious. Fortunately he's recovered now."