Porthen is one of three youngsters who will play in their 'first really big Test match', said Rassie Erasmus.
The Springbok scrum sessions prepare players for any eventuality so that nothing surprises them at game time, said Zachary Porthen.
The 22-year-old tighthead was speaking ahead of South Africa’s Nations Championship opener against England at Ellis Park on Saturday (kick-off 5.40pm).
The set-piece is expected to be massive between the sides, who both normally pride themselves on winning the physical contest.
Springbok veteran Ox Nché said he was looking forward to the clash, with young English players coming through eager to exert dominance.
The loosehead also said young Porthen, who has just three caps, had been a formidable opponent in their live scrum sessions at training.
Porthen will play from the bench while the tried and tested powerhouse, Wilco Louw, is rested.
Porthen is also joined on the bench by Eighthman Hanekom, 24 years old with one cap, and utility forward Jan-Hendrik Wessels, 25, with nine caps but playing hooker.
Head coach Rassie Erasmus said he hoped to see whether these three can implement what they learned in training in “their first really big Test match”.
“I think coach Daan [Human] tries to simulate getting into that dark space and almost make it more intense than a game,” Porthen said.
“So that when it comes to game time, we are not shocked by the intensity or what we go through.
“I don’t want to say too much but at scrum time we try go through different scenarios. We scrum with guys who can play in different positions. We incorporate that in training so that nothing comes as a shock.”
The youngster said he was absorbing everything he could at training. But talks with veteran Springbok props taught him that one can never stop learning.
“I spoke with some of the guys, and they said even they haven’t figured it out.
“There are so many things in terms of scrumming that you could neglect one, master one, and then neglect that again. We are trying to be on top of it all the time. I am taking it all in.”
Porthen volunteered to come on as tighthead for Gerhard Steenekamp during his third Test, against Wales last year.
He said he would happily do that again if it would earn him selection or help the team.
Bongi Mbonambi and Zachary Porthen after the Springboks’ win over Wales in Cardiff last year. Picture: David Rogers/Getty Images
He added that growing up, Frans Malherbe and hooker Bongi Mbonambi were his role models.
But he also admired Cheslin Kolbe and Eben Etzebeth “because of the way they uphold themselves outside of the rugby environment”.
