Uncapped prop Heinke van der Merwe, who plays for the Lions and the Cats, has been included in the South Africa squad for the clashes with Wales and the Barbarians.
In addition, Western Province utlity back Jantjes has been rewarded for his performance in this season's Currie Cup.
"It's a pleasant surprise," Jantjes told news24.co.za.
"There was some speculation initially that I could perhaps have been in the squad for the World Cup tournament, which didn't happen, so I wasn't really holding thumbs for this tour.
"Of course I wouldn't have minded being called up five weeks earlier, but Percy did an outstanding job."
Jantjes made his test debut in 2001, and last played for South Africa in 2005.
The 22-year-old Van der Merwe was called up to replace Cobus Visagie while the Boks were in Australasia for the Tri-Nations series earlier this year but was not used in either clash.
"It's every player's dream to be picked for the Springboks and I'm very excited about my inclusion.
"I was at home playing TV games on Tuesday when I received the call (from Lions coach Eugene Eloff) to tell me I was in the Bok squad. I actually wasn't expecting it," Van der Merwe added.
It is a much-changed Springbok squad to that which clinched the World Cup in France last month.
Os Du Randt and Bob Skinstad have retired while Percy Montgomery, BJ Botha, Jean De Villiers and Pierre Spies are all injured.
Butch James, Gary Botha and Ashwin Willemse were not considered as they have all joined foreign club sides and were subsequently not released.
The Springboks will play Wales in Cardiff on November 24 and the Barbarians on December 1 at Twickenham in London.
The team gathers in Johannesburg on November 12 and leaves for Wales on November 16.
Squad: B Botha, S Burger, B Du Plessis, J Du Plessis, F Du Preez, J Fourie, B Habana, C Jantjes, R Januarie, W Julies, V Matfield, J Muller, A Ndungane, W Olivier, R Pienaar, JP Pietersen, A Pretorius, D Rossouw, J Smit (capt), J Smith, G Steenkamp, F Steyn, A van den Berg, W van Heerden, CJ van der Linde, H van der Merwe.
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