They have taken that sense of annoyance and frustration out onto the training pitch this week, with the result being 'an extra edge' to the sessions as they look to hit the high standards they know they can reach against the All Blacks.
"There's been an extra edge in the forwards this week and there has to be. We're playing against probably the best side in the world and the pack needs to front up big time," said Plumtree, speaking at the squad's base in Carton House.
"As a pack New Zealand are the ultimate test. It doesn't get any tougher than this and we were irritated with our performance last week.
"We've promised ourselves that there's going to be less talk and more action. We were very disappointed with that performance (against Australia).
"We scrummed poorly. We didn't have too many opportunities, lineout wise, to drive but we put in one good drive (in the first half). But then we conceded a soft try as well in the driving (maul), which I know the boys are very frustrated with and fuming with.
"We planned to stop that, we knew it was coming. The plan we had in place, we didn't perform. That makes it doubly irritating I guess."
The New Zealand native is well placed to judge the quality of this current All Blacks side. Understandably, he rates them highly but Ireland will get chances against them and they simply have to put them away.
"I can remember some pretty good All Blacks sides from over the years, but this side is certainly right up there. I think this All Blacks team is just one team you don't want to miss when they're on TV, so that's a compliment for them.
"They play good rugby, they entertain, they've got great players, they're well organised, theyve a good coaching group and they certainly are a real challenge for any side that runs out against them. Luckily for us, we get that chance this week.
"We've got to work hard to create opportunities. Joe (Schmidt) is a smart enough coach to see there are opportunities there. Every side is at breaking point at some point if you apply enough pressure and it's making sure that we find those bolts this week."
Frustration comes to mind once again when recalling Ireland's 22-19 loss to New Zealand during the 2012 summer tour. That Christchurch cliffhanger, which saw Ireland lead 10-9 at half-time and fight back to level at 19-all, was decided by a late drop goal from Dan Carter.
It was really one that got away as Ireland's forwards set the tone that day by putting in a hugely physical 80 minutes. They took the game to the hosts, putting them under pressure at set piece time and the breakdown.
"I think they should have won that Test match, they should have created history that day," was Plumtree's assessment, with Ireland's record against New Zealand now standing at 26 defeats and one draw (1973 at Lansdowne Road).
"It was in New Zealand and Christchurch is one of the toughest places to win. So the boys have got to take something out of that game and take it into this one.
"With every performance, you'll see an opportunity depending on how much pressure has been applied."
The clinical edge that was so lacking against Australia simply has to resurface if Ireland are to have any hope of creating history against the All Blacks this weekend.
Both in defence and attack, they can ill-afford the mistakes that littered their display against the Wallabies. Schmidt's men coughed up four tries last Saturday as the tourists gleefully took advantage of some sloppy Irish defending.
Plumtree agrees they were 'soft points' to concede, admitting: "We leaked four soft tries which the Australians didn’t have to work too hard to get. They took us wide once, back to wide and the next minute they were scoring under the posts. That's unacceptable.
"There was a driving lineout that we knew was coming but we didn't deal with it and that was disappointing.
"The try they scored from the scrum was a poor scrum from the forwards because we didn't apply any pressure and we got it wrong defensively, that allowed Quade Cooper in - and those were soft points.
"Any point we got, we had to work for and one thing that annoyed me about playing against the Australians was that they gave away penalties every time we got behind them consistently.
"We only got three (points) when it might have been seven and I think Australia learned that from playing New Zealand and South Africa. It is disappointing that we didn't look after those situations better."
Meanwhile, the Irish management remain hopeful that their three injury concerns - 2013 Lions Jonathan Sexton (hamstring), Rob Kearney (rib) and Brian O'Driscoll (calf) - will train before the team announcement on Friday.
Plumtree explained: "We'll make a call on Johnny later in the week, he didn't train today (Wednesday). He had a run yesterday, about 50-60%, and he had a rest day today, so we'll see how he goes on Thursday.
"Rob trained today, I haven't spoken to him since training. We didn't do much contact. Brian hasn't trained either but we have the luxury of an eight-day turnaround.
"The reality is that Joe would have liked them to have trained the last couple of days, but the reality of it is that they haven't been able to. We still have two sessions and if they can get back on the field on Friday we'd be pretty happy with that."