Former Springbok scrumhalf Joost van der Westhuizen insists he has not been placed on oxygen.

Van der Westhuizen was diagnosed with the most severe form of motor neurone disease in 2011 (amyotrophic lateral sclerosis), and was given between two and five years to live.

Yet, Van der Westhuizen has defied those odds, and devoted himself to aiding sufferers of the fatal disease through his formation of the J9 Foundation.

Joost’s brother, Pieter, told Huisgenoot that he has been on oxygen for some time.

'It’s incredibly tough. He’s not doing well, but he keeps on fighting,' Pieter said.

However, on Friday Joost took to Twitter to set the record straight.

'Thank you everyone for caring. I just want to make something clear. I’m NOT placed on oxygen. I’m fine and still going strong!!!'

Van der Westhuizen played in 89 Tests for the Boks between 1993 and 2003, and is widely regarded as one of the game's great scrumhalves.

Photo: Carl Fourie/Gallo Images