Ngoma was signed in January from Cape Town City after missing the first half of the season through injury and continued to struggle with a knock at Chloorkop.
Mosimane brought Ngoma on as a substitute in the CAF Champions League defeat to AS Togo-Port on Tuesday, but recently admitted that the left winger has to work on getting back to full fitness before he can be considered for a place in the starting line-up.
“When Aubrey Ngoma came, remember he was out for six months. So it takes time,” Mosimane tells KickOff.com.
“We are just a little bit unfortunate that the key players we want have injuries that they come with or they have not been playing for some time. Toni [Silva] had issues with his team in Greece, with non-payments and then he decided not to play. He had to wait for the season [to end]. [Jose] Ali Meza had a slight injury and he was out for three-and-a-half months.
“He [Ngoma] has started well with the pre-season. We can’t say he is fully fit, but at least he has started with the programme. And we have also been playing him at left-back. You can’t play one position when you are at Sundowns and in the modern era. If you play one position, then we have to carry more numbers in the squad.”