The first Test of the series takes place in Pretoria on Saturday with the second to be held seven days later in Durban.
With the retirement of Keith Earls after the World Cup, and the injuries sustained by Connacht’s Mack Hansen that have kept him out of the green jersey since that tournament, Nash has quickly moved up Ireland’s depth chart in the back-three positions.
He made his international debut in a World Cup warm-up against Italy last August, but did not make the trip to France once Andy Farrell trimmed his squad for the tournament.
Come his key role in the Six Nations, he says he was still getting to know his new team-mates.
“Six Nations helped me a lot, [I have] a lot more calmness coming into the international stage,” he added.
“Getting to know the lads was probably the main thing for me. Knowing what they’re doing on the pitch, but the off the field relationships are massive and what helps the team be stronger.
“It’s been class to get over here, spend more time with the lads and get to know people more.”
