WARNING: This clip is not for the faint-hearted.

Venezuelan footballer Juan Carlos Carvajal suffered what looked like an agonising knee injury while playing a match last week – and had to be treated on the pitch by emergency personnel.

The player suffered a dislocated knee cap, which had visibly twisted round to the outside of his leg.

Correct medical treatment for this injury involves a trained medic manually moving the kneecap back into position when the leg is straightened.

The sooner this is done the better – so when the nearby Miranda State Fire Marshals were called to the pitch they moved his patella back into position there and then.

Carvajal’s club, Club de Muchachos Nueva Casarapa, posted a video on their Facebook page showing it being done.

The player was clearly in extreme pain as the medic gently straightened his leg until the knee cap popped back into its correct position.

He was then brought to hospital for further treatment. His club thanked the emergency services, saying: “The firefighters of Miranda State treated him in record time … Thank you friends and may God bless you.”

They added: “Get well soon Juancho.”