Erasmus believes that the team 'needs' the 'tough' schedule and admitted that there will be some chopping and changing once again as South Africa targets a three-peat of World Cup titles.
The Springboks will play a warm-up match against a non-Test team before they face Italy and Georgia in July. Springboks general manager Charles Wessels also stated the opposition will be the Barbarians, with the fixture taking place on Jun 28, with the venue for the match still to be confirmed.
Additionally, he stated that negotiations were taking place for another yet-to-be-determined official Test match ahead of the July Series.
"During the campaign, we will play 13 Tests as well as the Barbarians on Saturday, 28 June prior to the opening of the July window," Wessels said.
This could mean that the Boks head to the Northern Hemisphere before their three home Test matches, which was the case last year too as they faced Wales in a one-off international at Twickenham Stadium ahead of the back-to-back matches against Ireland.
The Barbarians played on the same day as the aforementioned meeting between the Boks and Wales as they defeated Fiji 45-32.
Because that fixture will be outside of the official window, Erasmus will not be permitted to select any players plying their trade with Premiership or Top 14 clubs as well as overseas-based URC teams.
Erasmus addressed the additional fixtures at a press conference in Cape Town on Wednesday with the extra two games taking the Boks' schedule to 15 matches, one of the longest seasons since 2007 according to the coach.
"We are hoping that we will get 15 matches, we have almost confirmed every single one, not all the venues though," he told reporters.
"It's a really tough season, just go look at our draw, 2022 was really, really tough but now we have 15 matches and I think it's only the second time in history that we will play that many - 2007 was 17 matches.
"So it's the first time in a long time and I think we need that because we still want to filter and sieve some players, give a lot of them opportunities whilst winning because I know that I won't be sitting here if we just chop and change and don't win."
The match against the Barbarians will be the first time that the Springboks have faced the invitational team since 2017 when Allister Coetzee's drew 31-31 with the Baabaas.
A year later, Erasmus coached the Barbarians leading the side to a 38-35 victory over Argentina.
Springboks 2025 fixtures
28 June: Barbarians v Springboks venue TBC
5 July: Springboks v Italy - Loftus Versfeld, Pretoria
12 July: Springboks v Italy -- Mandela Bay Stadium, Gqeberha
19 July: Springboks v Georgia - Mbombela Stadium, Nelspruit
16 August: Springboks v Australia -- Ellis Park, Johannesburg
23 August: Springboks v Australia -- DHL Stadium, Cape Town
6 September: New Zealand v Springboks - Eden Park, Auckland
13 September: v New Zealand v Springboks, Wellington
27 September: Springboks v Argentina -- Kings Park, Durban
4 October: Argentina v Springboks - Twickenham Stadium, London
8 November: vs France - Stade de France, Paris
15 November: vs Italy, TBC
22 November: vs Ireland -- Aviva Stadium, Dublin
29 November: vs Wales - Principality Stadium, Cardiff