Robin McBryde believes that Wales will face "arguably the best side in world rugby" when they go for Guinness Six Nations title and Grand Slam glory on Saturday.
Ireland stand between Wales and them achieving a third Six Nations clean sweep of head coach Warren Gatland's reign.
It is Gatland's final Six Nations game before he steps down from his Wales post after the World Cup later this year.
Ireland can still win the championship, while England – who host Scotland at Twickenham this weekend – are also in the title mix.
But unbeaten tournament leaders Wales occupy pole position, knowing that a win at the Principality Stadium will be enough to land European rugby's biggest double prize.
"We know it will be a big test for us," Wales assistant coach McBryde said.
"We have put ourselves in a great position, and it's a chance in a lifetime for some of these boys, and that is not lost on anybody.
"We are facing arguably the best side in world rugby to do that on the weekend. It would be no mean feat in the Six Nations, and games can be decided on small margins and decisions.
"We have done exceptionally well to put us in this position, but it won't mean anything if we don't finish the job on the weekend.
"New Zealand have not played for a while, but I would say they (Ireland) are the team to beat at the moment.
"The (Wales and Ireland) players are familiar with each other, having been on numerous British and Irish Lions tours together.
"With that familiarity there is a respect for each other, and it brings an extra edge. It is a lot more personal when you want to beat the guy you know, and that will be the case on Saturday.
"There will be a lot of personal battles and scores to settle, and hopefully we will have some rugby being played as well.
"Both teams are used to playing on the big stage when something is at stake, and once you have tasted success you know there is no secret formula to it."
Gatland is due to name his team on Thursday, with McBryde reporting that full-back Liam Williams is "moving in the right direction" after going off injured against Scotland at Murrayfield last Saturday.
"He just took a little bit of a stinger on his shoulder," McBryde added.
"He is improving. His return to training is gradual, and there has been no contact, and we will gradually increase that to see how he is, but everything is moving in the right direction at the moment."
McBryde, meanwhile, readily acknowledges the threat posed by Ireland fly-half Johnny Sexton, and he also underlined a need for improved discipline, with Wales considerably weaker in that key area against Scotland than they had been in defeating England two weeks earlier.
"It is important we put a number of their decision-makers under pressure," McBryde said.
"The spine of their team is a very strong one and you can't single out one individual.
"Having said that, Johnny is very influential on the game, as any world-class 10 is. We have to go about our work legally and ask questions of them.
"We have got to be disciplined. That's one thing we have got to improve from the weekend against Scotland because we gave them numerous opportunities within 10 metres of our line.
"As Ireland showed against France, if you give them the same opportunities, they will take them."
