Dylan Mostert, Teaghan Gauche and Siyanda Mwandla are the latest golfers to withdraw from the tournament after Darren Fichardt, an 18-time winner on the local Sunshine Tour, tested positive for Covid-19 on Tuesday.
Last week, the DP World Tour, formerly called the European Tour, announced it would no longer sanction the event, due to travel restrictions placed on South Africa following increased concerns over the latest Covid-19 variant.
The DP World Tour had previously cut the Joburg Open to 54-holes, from the regular 72-holes, to help non-South African resident players and staff return to their home countries.
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Due to the travel restrictions, The Alfred Dunhill Championship scheduled from December 9-12 was canceled.