Jean Kleyn: I was a 'very different person' when I played for Ireland

While the Springboks voted against the eligibility law changes that made Kleyn's switch possible, they were quick to take advantage when they came into effect by drafting in the second-rower, who played five Tests for Ireland in 2019.

The move made sense after the Munsterman showed strong form in his side's impressive run to winning the United Rugby Championship title only to be overlooked by Ireland.

However, it puts the star in a unique position as the two teams lock horns in a Rugby World Cup for the first time in history on Saturday.

Kleyn, who has been named on the bench for this weekend, acknowledged his time with Ireland but insists that things are different now.

"The two are quite detached to me. I was a different person back then," Kleyn told reporters.

"I was much younger, I paid a lot more attention to what people said compared to now, especially in the media.

"There was massive pride for me to represent Ireland back then and now I have a massive opportunity to be able to represent my country of birth."

The change of the laws to allow players to make the switch in the way Kleyn has came with some criticism, but the lock is not concerned and is only focused on his inner circle.

"It's a lot of outside noise to me, I try to focus on what happens inside the team and my family," Kleyn said.

"I try to focus on the internal conversations I'm having.

"I know the reasons why I do things and I know those reasons will change," he added.

What the situation does offer for the Springboks is an interesting insight into the Irish camp through Kleyn's experience having played with a large contingent of their squad.

The South African singled out Johnny Sexton and Peter O'Mahony as two players in the squad who power Ireland's meticulous attention to detail.

"They're an incredibly clinical team, that's the thing with the Irish, they tend to nail the details," Kleyn said.

"Guys like Johnny and Peter are quite serious about driving the detail and not making small mistakes.

"They drive precision and execution. We'll have to pitch up on the day," he added.

Saturday night's blockbuster clash at the Stade de France in Paris could decide the winner of Pool B, with the Springboks virtually certain of securing top spot if they manage to come out on top as they have already beat Scotland.

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