Mokoena recently joined Manqoba Mngqithi and Alex 'Barnes' Bapela as assistants to Mosimane.
Mokoena sat on the bench when the Brazilians beat University of Pretoria 2-1 in a Telkom Knockout last-16 tie in Tshwane on Saturday.
"Rhulani is officially assistant coach of the senior team. We promoted him from the development team where he has done exceptionally with the U-19s," says Mosimane.
"Rhulani is something to watch... watch this space, he is the future. He is a good coach and he knows his stuff. He is young and a little bit raw but he is quality."
'Jingles' believes young coaches should be given opportunities
"We need to promote from the youth. We need to show and encourage coaches in youth programmes to say that the future is bright. We promoted Rhulani because he deserves it, he must earn it.
"I was given a chance as coach around the age of 33. I need to give other guys a dream and a vision so that they can also taste it," he adds.