12 Dec, 14:42
Prop Cian Healy is expected to miss the start of the 2014 RBS 6 Nations after undergoing surgery on his injured ankle on Wednesday.
A number of top officials have quit the game following a disastrous performance in last year's World Cup. State broadcaster SABC reported that sweeping changes in had been approved at a recent board meeting, but did not give any details.
SARFU said on their website: "Mr du Plessis has indicated in a letter to the chairman of the board, Dr Theunie Lategan, that he could not guarantee what his level of contribution would be in future following the suggested changes at the bosberaad (meeting) and therefore felt it appropriate for him to stand down."
Du Plessis' departure follows a series of resignations after the Springboks were ousted from the World Cup in a humiliating quarter-final match when they lost 29-9 against New Zealand. Skipper Corne Krige, coach Rudolf Straeuli, SA Rugby managing director Rian Oberholzer and SARFU president Silas Nkanunu have since quit.
SA Rugby was hit by another scandal in January when financial auditors found that one million rand (143,000 dollars) had been stolen from its coffers. Two staff members were subsequently been suspended.