The Official Fanpage, J9 Foundation has confirmed that Joost has passed away.
They posted on Facebook:
It is with great sadness that we confirm the passing of Joost. He passed away in his home surrounded by his loved ones.
He will be sorely missed
Xx
Joost passed away at his house with his loved ones around him. Jacaranda FM News spoke to the former Springbok's family last year.
His father, Gustav, fondly remembered the first time he saw his son in the Springbok jersey.