The former Ajax Cape Town man came on as substitute to replace Tiyani Mabunda during the CAF Champions League Group A match against Lobi Stars at Lucas Moripe Stadium on Saturday, and played in the defensive midfield role.
Mosimane has revealed that he has been using Coetzee, who did not look out of place, as a number six in training.
Coetzee, who has been called up to the Bafana Bafana squad for the upcoming Africa Cup of Nations qualifier against Libya, is comfortable when in possession and is a good passer of the ball.
“The change that we made on Mabunda was that he got yellow card in the second minute and we didn’t want to risk. So that’s why we put Riva as a six,” said Mosimane.
“We have been training him to play six and he came on as six… top six and very good. Also I could have played Oupa [Manyisa] because it was a free flowing game, but the Nigerians are big and we don’t have height and that’s why we played Riva to help us on set pieces.”
Sundowns, meanwhile, take on Maritzburg United in the Absa Premiership at Harry Gwala Stadium tonight (19h30). A win for the Brazilians, who have a game in hand, will take them to the top of the standings, with a three point lead.