It has been a meteoric rise for Romano, who was the fourth-ranked lock for the Crusaders when when he made his Super Rugby debut last year.
Romano, 26, was a late bloomer in rugby - he was actually making his mark in cricket in Christchurch as a fast bowler - but he has made up for lost time.
He made his debut against Ireland and has retained his place for the two Tests against Australia and the clash with Argentina last weekend, impressing with his robust, physical approach and his ball skills.
"It's right up there in terms of career highlights," he said in reference to his first test against the Springboks.
"The Aussies are obviously our enemies but the 'Boks are our traditional opponents and are tough in terms of their attitude and physicality. It's an exciting challenge."
Romano said the tough forward-orientated Test against the Pumas was good physical and mental preparation for the Dunedin showdown.
Romano was a strong presence at the lineout in the Wellington win and said he was looking forward to the aerial battle against the Springboks.
He said: "All their Super (Rugby) teams have got very good lineout forwards. They're big men. Victor (Matfield) and company left them in pretty good shape. It's something we're really excited about. We'll try to get on top of them in the lineouts so it should be a good battle.
"It probably does help that you play the Africans and Aussies in Super Rugby and you've got a general idea of their forward methods.
"But the physical side of it doesn't get any easier. They're a big team and their players love confrontation."
Romano said the breakdown would be a crucial area in Dunedin.
"I think every team tries to disrupt at the breakdown. If you slow down the opposition ball, you allow your defence to set.
"We need to do our job properly in and around the breakdown and give our halfbacks decent protection. We need to really work on that."