The training group, which was announced last Saturday, had a handful of training and gym sessions as well as several team meetings as they gear up for their first Test of the season against Australia at Loftus Versfeld on Saturday, 8 July.
The training camp will run until Friday 30 June, with the team switching into full Test-match mode the following week.
“We are very happy with the opening week of our training camp,” said Nienaber.
“It was great to have the players here, and to get them back into the swing of things both in terms of the intensity of our training sessions and to get everyone aligned with our structures off the field.
“This group comprises players from 19 clubs, so it was vital to get everyone on the same page in terms of how we do things.”
Nienaber added: “The players were very excited to see one another when we got together on Sunday and to get the season underway.
“As coaches we are also pleased with the quality of our training sessions and to see how determined the players are to participate in the Castle Lager Rugby Championship and stake a claim for places in the Rugby World Cup squad.”
The current squad – which will be expanded to 41 players from Sunday with the addition of the experienced Elton Jantjies, who will provide flyhalf cover due to the injuries suffered by Handre Pollard (leg) and Damian Willemse (knee) – had their last field training session for the week on Friday and will assemble again on Sunday after a well-deserved rest over the weekend. They will be joined by utility forward Jean-Luc du Preez later this month.
The Boks will begin their 2023 season on Saturday 8 July, against the Wallabies, which will be followed by a Test against New Zealand at Mount Smart Stadium in Auckland (15 July), before returning to South Africa for their closing match of the abbreviated version of the tournament against Argentina in Johannesburg (29 July).
They will then play three Rugby World Cup warm-up matches: against Argentina in Buenos Aires (Saturday, 5 August), Wales in Cardiff (Saturday, 19 August) and New Zealand in London (Friday, 25 August) before departing for the Rugby World Cup in France.