Coach Warren Gatland says Wales' players dislike their Irish rivals more than any other team in the Six Nations.
Gatland made his comments ahead of Saturday's crunch game in which Ireland bid for the Grand Slam and Wales for the Championship and Triple Crown.
Gatland said: "Probably, out of all the teams in the Six Nations, the Welsh players dislike the Irish the most.
"Players' experiences against Ireland haven't always been the greatest, so they are very motivated."
Gatland had a 38-Test reign as Ireland coach between 1998 and 2001 and his comments came after he named a team showing eight changes from the line-up that fumbled its way to a 20-15 win against Six Nations Wooden-Spoon favourites Italy last weekend.
It's about winning the game first, win the Triple Crown, deny them the Grand Slam and then see what position we are in
Warren Gatland, Wales coach
Ireland are on the verge of winning the Grand Slam for the first time since 1948. But Wales could retain the Six Nations trophy if they beat Ireland by 13 points or more.
They last achieved that at Ireland's expense 26 years ago - while a victory of any description would secure a third Triple Crown in five seasons.
Gatland added: "It's about winning the game first, win the Triple Crown, deny them the Grand Slam and then see what position we are in.
"There is a lot of pressure and expectation on the Irish team to come to our back-yard and perform.
"After the Scottish game [on Saturday], the Irish players were an hour-and-a-half in the changing room celebrating and singing, so they were clearly happy where they were at.
"It's how they handle that pressure. There has been expectation on them over a number of years and in a couple of World Cups as well.
"At international level, when there has been that expectation either to perform in Six Nations tournaments or World Cups, they've sometimes faltered a little bit.
"It will be interesting to see how [coach] Declan [Kidney] handles that and how the players handle that this week.
"They've performed well in this Six Nations, but we're at home with a massive crowd behind us.
"If you go back to the autumn, they [Ireland ] were talking themselves up a lot before the All Blacks game - and they really performed poorly in that game.
"We've got to really concentrate on ourselves and put them under as much pressure as we can."
Reflecting on events in the Eternal City, Gatland said: "I've been criticised for the number of changes I made, and in hindsight maybe we made too many changes.
"I am not afraid to put my hand up and say maybe it was the wrong decision. Tactically, we got some things wrong against Italy.
"We feel we haven't played as well as we could have done in this Six Nations and we want to address that.
"To win the title again would be a massive achievement. If we play to our potential on Saturday, we are capable of winning and winning well."
He added: "With a healthy head-start, you have to say Ireland are probably favourites to take the title.
"But we are confident we can come up with a win - and who knows what will happen if we can get ourselves ahead in the game and that Millennium Stadium factor begins to kick in?"
Wales: Lee Byrne; Mark Jones, Tom Shanklin, Gavin Henson, Shane Williams; Stephen Jones, Mike Phillips; Gethin Jenkins, Matthew Rees, Adam Jones, Ian Gough, Alun-Wyn Jones, Ryan Jones (capt), Martyn Williams, Andy Powell. Replacements: Huw Bennett, John Yapp, Luke Charteris, Dafydd Jones, Warren Fury, James Hook, Jamie Roberts.
Ireland: Rob Kearney; Tommy Bowe, Brian O'Driscoll (capt), Gordon D'Arcy, Luke Fitzgerald; Ronan O'Gara, Tomas O'Leary; Marcus Horan, Jerry Flannery, John Hayes, Donncha O'Callaghan, Paul O'Connell (capt), Stephen) Ferris, David Wallace, Jamie Heaslip. Replacements: Rory Best, Tom Court, M O'Driscoll, Denis Leamy, Peter Stringer, Paddy Wallace, Geordan Murphy.
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.