The Urban Warriors have already signed Joaquim Lupeta from BidVest Wits, Eric Chipeta from Chippa United as well as Thabo Mosadi from Tuks on a permanent basis.
A source close to Ajax confirmed that Pietersen will be signed in the next few days after he gave a good account of himself in training.
"Roscoe has impressed during his first week of training with the Urban Warriors," said the source. "He is a quality player despite the fact that he doesn't have the pace anymore.
"One also needs to realise that he had a few injuries which kept him on the sidelines. That said I have no doubt that he will definitely add value to the squad."
Pietersen, who was loaned out to the NFD outfit Vasco da Gama from SuperSport United last season, will in all liklihood be drafted in as a squad player.
Whilst he will probably be providing back up for captain Travis Graham and Ndiviwe Mdabuka in the engine room, at only 27-years-old Pietersen still has a lot to offer.
"He is a very experienced and versatile players and can slot in defense as well should need be," the source continues.
"All in all he should be a good signing for the club and from what I know this will probably happen in the next few days."