Heyneke Meyer rates Jonathan Sexton right "up there with the best".
The Springboks coach's concern is Sexton will do to them what they have spent over a century doing onto others.
"What I like about him is (that) he is big, he is a good defender, he is a great attacker and he is a very good tactical kicker," said Meyer.
"If you look at the Six Nations, Ireland had the best scrum, lineout as well, but the one area they were way ahead was the tactical kicking and the contestable kicking.
"It is one thing we struggled at against the All Blacks.
"It was a South African strength and we've moved away from that and we are really working on it.
"One of the dangers is that if he's going to turn us and put us into the corners, it is going to be a long day for us.
"We can't get out of that."
Even so, Meyer has backed Handre Pollard to stand up to Sexton in the battle of the playmakers.
The affable coach made light of his decision to hand 20-year-old Pollard his international debut in t he Rugby Championship.
"Back home, people see me as this dull, Afrikaans, stupid, conservative guy," he said in jest.
"I have always been a risk-taker, I truly believe in a 50-50 I go for the youngster that I believe can be superb."
The emergence of Pollard was sealed by his two tries against New Zealand in the Rugby Championship.
"I knew it was a huge risk against the All Blacks," he said.
"I also knew he was an unknown force
"But you can't just play youngsters and throw them to the wolves.
"You have to balance that with experienced players around him."
This is where the know-how of captain Jean de Villiers will come into play as a 13-year international veteran.
Meyer has shown respect for Ireland by opting for the same side that beat the All Blacks last month.
South Africa: W le Roux; C Hendricks, J Serfontein, J de Villiers (capt), B Habana; H Pollard, F Hougaard; T Mtawarira, B du Plessis, J du Plessis, E Etzebeth, V Matfield, M Coetzee, T Mohoje, D Vermeulen.
Replacements: A Strauss, T Nyakane, C Oosthuizen, B Botha, S Burger; C Reinach, P Lambie, JP Pietersen.