Chris Henry insists Ireland's training has taken on a combative edge as they approach yet another critical showdown with Argentina.
Victory at Aviva Stadium on Saturday will secure the winners a place in the top eight of the IRB rankings, which are being used to determine the seedings for the 2015 World Cup.
The losers will slip into the third tier of seeds for next month's draw and face the possibility of being selected in a pool containing two major nations, and Henry said: "It's (training) been bubbling this week. Not everyone trained on Monday, but it definitely started to bubble yesterday. That was the edgiest training session of this campaign."
If the prospect of dropping down the rankings alone is insufficient to inspire Ireland, flanker Henry believes the anguish of their 16-12 defeat by South Africa in the Guinness Series opener should spur them on.
"The atmosphere's boiling up. Losing two weeks ago was one of the hardest moments I've had to face in my rugby career," the Ulster openside said. "Losing at home, it was hard to take. I didn't think it would hurt as much, but it did. Everyone put everything into South Africa and that was disappointing, but we're not far off.
"In teams I've been involved in before, if you're edgy at this stage of the week and you're getting tetchy with your team-mates, then that's a good sign.
"Last Saturday's win against Fiji wasn't a Test, but it was still great to score tries and enjoy rugby again.
"If we can get the balance of that enjoyment and the hurt of South Africa, we'll be in a good place.
"As players we're not stupid, we know what's at stake on Saturday, but for me it's about Ireland playing at home.
"We don't want to lose at Aviva Stadium again and that's what we're holding on to."