Promoter and manager Enoch Nxumalo - who also trains the Pietermaritzburg boxer at his Nxums Boxing Gym in Soweto - made it clear yesterday that if Ngubane fails to defeat Esther Mashiya in Welkom, then she might as well wave goodbye.
"I told her that this is a must-win fight for her. I made it clear that I cannot continue working with a loser," Nxumalo said.
"From my observations in the gym she looks the part."
Ngubane has an unimpressive CV which reads two wins, three defeats and two draws.
Mashiya currently holds the junior middleweight belt. She last fought on March 27 in Sweden where she failed to win the Women's International Boxing Association and Universal Boxing Organisation junior middleweight belts from Mikaela Lauren.
Mashiya's trainer Peter "Black Chinese" Shakong yesterday predicted a win for his charge on Sunday.
"We know what to expect from Mapule. We've beaten her twice before and the result will stay the same," said Shakong.
This grudge fight will top promoter Fezile Mabuya's "Women Only" bill, celebrating Women's Month.
In the main supporting bout Babalwa Nongqongotho and Mellisa Miller will meet in the official junior bantamweight title eliminator.