Family and friends rush to hospital as Joost admitted to ICU in a critical condition.

Family members have rushed to hospital as former Springbok Joost van der Westhuizen was admitted to ICU in a critical condition.

 A statement on the J9 Foundation's website confirmed he was in hospital.

"The family and friends of Joost ask that you all pray for Joost. He was taken to hospital earlier today and is in a critical condition."

Two weeks ago it was revealed that Joost was now on an oxygen machine. At the time it was reported he was on the machine to survive, but Joost downplayed these reports, saying he was "doing well under the circumstances."

He was diagnosed with a form of MND in 2011 and has spoken publicly about his illness, insisting that he will fight until the end.