Replacement scrum half Gareth Davies runs at the heart of the Springboks defence.
Warren Gatland is hoping his Welsh side will learn the lessons of their 38-16 defeat in Durban by the time they line-up in Nelspruit on Saturday for the second Test against the Springboks.
"We were outmuscled physically in the first half. The pace, intensity and physicality the Springboks came with in the first half we really struggled to cope with," admitted Gatland.
"We need to learn from today's game and tidy up some things for next week. If we can be more clinical then maybe the gap will be closer next week.
"I was a bit like the game against Australia two years ago. We didn't look fit enough out there in the first half.
"We got to grips with the pace of the game in the second half, but we are really disappointed. We have to look at that second half performance and we have to work hard on the breakdown and be more physical in the collision area.
"Because we were very poor in the first half we need to feel disappointed over the next 48-72 hours. But then we need to get back on the horse, work hard and be much better next weekend."
Wales skipper Alun Wyn Jones blamed his side's inability to take their chances in the early exchanges for a poor first-half performance.
"We had four opportunities in the first-half and we didn't complete them. They had two and took them both," said Jones.
"The damage was done in the first half - we were lacklustre in keeping the ball and we can't do that. When we did keep the ball we tested their defence."
Nearly 40 players were involved in the first Wales Under 18 training session of the season. WRU National Performance Manager Gethin Watts is excited at the potential shown by the group and expects the Regional Under 18 Championship to hone their skills even further.