Nienaber will vacate his role after the World Cup in France, having agreed a move to Irish side Leinster as a senior coach, while Jones joins the England set-up under Steve Borthwick (43).
But any thoughts their might be a mass exodus have been allayed with Bok assistant coaches Mzwandile Stick (38), Deon Davids (55) and Daan Human (47) all signing new four-year deals, and head of athletic performance Andy Edwards following suit.
"They have all come a long way as a coaching team under the guidance of Rassie (Erasmus), as director of rugby, and I am confident that the continuity in our coaching staff will bode well for the Springboks for 2023 and the following seasons," SA Rugby CEO Rian Oberholzer said in a media release on Wednesday.
"It was our ambition to retain all the current coaching staff in recognition of the excellent work they have done over the past six years regardless of the outcome of the Rugby World Cup later this year, and we are pleased that most of them have agreed to continue with the team.
"The planning to confirm a successor in the title role of Springbok (head) coach remains ongoing in the background, while Rassie’s services are tied down to the end of 2025 at the very least."
The Boks open their 2023 season with a home Rugby Championship fixture against Australia in Pretoria on July 8.
