Going twelve rounds with South Africa must be something similar to being on the end of Mike Tyson's punches for every one of them.
In the case of rugby, you have to be able to dish it out the punishment and take it for 80 minutes.
Ireland have wounded the Springbok. Is it a mortal blow? Or is it merely the signal for South Africa to take the upstarts seriously?
Sadly, the answer will come at altitude in Johnannesburg where Ellis Park can jeopardise the God-given right to exhale freely.
The Irish will have to take the breath away in a similar fashion to last Saturday.
It will do their cause the world of good if they can keep fifteen on the field for the entire match.
While greed can be classed as good on Wall Street, fear is the fuel that will fire Ireland's engine.
"We know we're at our best when we're a little bit fearful of what the team we're going to be facing is about and what they're capable of," said Rhys Ruddock.
"We know that South Africa are probably better than they were last week and we know they're a difficult team to beat when we're on the top of our game.
"All the focus is going to be on preparing ourselves to the best of our ability, having a clear plan going into the game and being able to execute under the pressure that we're going to feel on Saturday."
The loss of CJ Stander to suspension would have been greeted with mixed feelings by the Leinster forward.
It isn't the way Ruddock would have wanted to gain favour.
Once it happened, it became an opportunity, just like any other, to be a part of history-making story and to make a case for regular inclusion.
He is expected to make the cut when the team is announced this afternoon.
The six-minute cameo Ruddock had in the first test was 74 shorter than he would have wanted.
"Every time I play against the South Africans, it is something that you probably notice more than any other team; just the physicality of the game," he noted.
"In terms of the way we played, we probably brought an added physicality and that's got to be the focus again this week, in order to be able to stick with a team like South Africa."
Ireland were not confronted by the monster South Africa was made out to be in the first test.
The coach Allister Coetzee, the general public and the players picked will not allow that to happen again in this series because it is stitched into their DNA.
"We are probably expecting South Africa to lift their level of physicality," he said.
"We know that if we can improve that small margin, maybe with 15 on the field, and be able to stick to our systems defensively, we can hopefully cope with that physicality."