Ireland play England in Dublin in what is already shaping up to be the Six Nations decider on just the third weekend of the championship.
The teams go into the game as the only undefeated countries with this meeting being the biggest hurdle each has to overcome in their quest for a grand slam.
Lancaster’s men have already been to Cardiff in this tournament to defeat Wales and silence the Millennium Stadium crowd and he says a team growing in maturity and belief is not afraid to do the same in the similarly daunting environment of the Aviva Stadium.
“Ireland have won their last nine games, they’ve got nine British Lions blah de blah de blah,” said Lancaster.
“I’m not saying that to make them favourites, but we’ll be ready to match them.
“Dublin is as intimidating a place as Cardiff. It’s a very difficult place to go and win.
“Sometimes when you’re playing against Irish teams you feel like you’re playing against 16 or 17 because of the energy that they bring.
“People like Paul O’Connell, who’s an inspirational leader and captain, will be at his best in his pre-game messages to his players. So it will be as difficult a game as we’ve had in a long time.
“It would be nice to repeat what we did in Cardiff, especially the second half.
“One of the keys to our Cardiff performance was that we went in with a strong sense of belief that we could win there, but the players needed to deliver on the day and they did that.
“We need to have the same sense of belief, which we do, going into the game, but ultimately it will come down to the 80 minutes.”
Whoever wins tomorrow will be installed as near certs to win the championship, particularly England, who have home games against Scotland and France to come, neither of whom have offered much resistance on recent visits to Twickenham.
But Lancaster, whose England team have missed out on the grand slam and the championship by losing one game in each of the last three Six Nations tournaments, knows not to look too far ahead.
“We’ve got two away games and three at home this year; Ireland have to go away twice on the back of this,” he added.
“We’ve very, very close together in terms of recent records. While we won last year it was a Joe Launchbury tap tackle which saved us from losing the game so I think there will be very little to choose between the two teams.
“We’ve got France and Scotland to come. We’re not going to get carried away thinking about silverware at all.”
With that in mind, he will send England out tomorrow to try to hush the home crowd quickly, something the Red Rose have been working on in the two weeks since they defeated Italy despite a sluggish opening.
“It’s an important point that we have talked about throughout the last two weeks,” continued the former Leeds player and coach.
“Not just slow in terms of conceding points, but more importantly, make sure our energy is right and our line speed is good in defence and we are winning that gainline battle.
“I don’t think it’s a consistent theme with this team. But the last two games, to concede and then try and claw your way back is far harder, and against a team of this quality it’s more difficult.
“I certainly think both sides will be ready for the game. There’s no doubt about it, getting the emotion right on the day will be important because Ireland will be up for it.
“We need to match them in that area.”
Lancaster has made the first changes of England’s Six Nations campaign after naming Alex Goode and Jack Nowell in their starting XV to face Ireland.
Goode slots in at full-back after Mike Brown was ruled out earlier this week with concussion.
Nowell replaces Jonny May on the left wing for his first cap since making his five previous Test appearances during last year’s Six Nations, ending a near year-long absence due to shoulder and knee injuries.
Once again England are outnumbered in terms of caps, just as they were three weeks ago against Wales, but convincing his players they are more than capable of matching the Irish is a challenge Lancaster relishes.
“That’s the trick. It’s creating the belief within the team,” he said.
“That’s the art of coaching. You have to create the belief that the players will go out and win.
“Every game the players go into, they have to believe they can win. That belief has to be built on foundations.
“The last two weeks have been excellent, we’ve had two good wins, a settled team. We’ve worked on the systems and structures.
“And that’s why it’s a fascinating game. Ireland have had two good wins so I’ll be very surprised if neither team is ready for this game.”
As well as a grand slam and the championship, England are also out to prove to themselves and their detractors that they are capable of stringing successive wins together given the start of the World Cup on home soil is a little over six months away.
“I wouldn’t say it was the big lever going into this game, the big lever is dealing with the game itself and getting another win,” added Lancaster.
“But certainly the ability to go back to back, and back up wins on the bounce, is important.
“Records don’t count for anything when Sunday comes around.
“The margins between the teams will be very small, it will be decided on key moments.
“It could be discipline, a defensive error, a moment of brilliance – but it will be tight.”