Mosiako had since been released from hospital and was recovering at home.
Speaking to The Star, Mokopane said the altercation erupted at a cafe near the campus, after Mokopane asked three men to stop insulting the cashier.
"When I went outside they were waiting for me. They started hitting us, even when we fell to the ground," Mokopane said.
He said the initial attack stopped when police showed up, but the police would not offer help to the pair.
"When the police came, I told them these guys are assaulting us. But they didn't listen to our story. We understood that they wouldn't help us and ran away."
They were then attacked closer to the campus, and Mosiako was knocked unconscious. He was rushed to hospital with head injuries.
Mosiako was due to travel to Algeria next month for the African Championships, however Mokpane told The Star his training partner was worried he wouldn't be able to perform as well going forward.
"He's nervous about (the prospect of) not performing. I can see he's stressing a lot," Mokopane said.
A case of assault with intent to do grievous bodily harm was opened, however police said at the weekend the attackers were yet to be identified.
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