The extraordinary footage appears to show a dramatically slimmer Pistorius enjoying a penalty shoot-out competition with Radovan Krejcir, who was last month charged with murder.

The disgraced sprinter, who was jailed for five years for killing his girlfriend Reeva Steenkamp, has struck up an unlikely friendship with the Czech fugitive since they became neighbours on the hospital wing at Kgosi Mampuru prison in Pretoria.

In the 90 second clip, South Africa's two most notorious prisoners are seen taking turns to play striker and goalkeeper in the facility's concrete yard which they seemingly have to themselves.  

The footage, shot from above on a mobile phone reportedly by a convicted robber, was published today by South Africa's Daily Sun newspaper. 

The pictures appear to support recent reports that the double-amputee has slimmed down dramatically since his incarceration four months ago amid fears of poisoning by other prisoners.

According to jail sources, the shamed athlete is surviving on tins of baked beans, pilchards and an African vegetable dish called 'chakalaka' bought at the prison tuck shop after spurning his rations.

Wearing trainers, grey shorts and a white, unbranded T-shirt that appears to swamp his lean frame, the 28-year-old's thin arms protrude from its sleeves. 

The images are in stark contrast to the muscle-bound track star who made history at the London Olympic games by competing against able-bodied athletes.

During the day, Pistorius is required to dress in the regulation orange jump suit which is issued to all inmates at the jail. 

(dailymail.co.uk)