Joe Schmidt insists Jordan Larmour and Andrew Conway's "contagious" exuberance can spur Ireland back to their best in the crucial World Cup opener against Scotland.
Leinster speed king Larmour faces the biggest challenge of his fledgling Test career when starting at full-back for Ireland's Pool A clash in Yokohama.
Munster flyer Andrew Conway has slotted onto the wing, and his aerial prowess will doubtless boost Larmour as the 22-year-old prepares for just his seventh Test start.
Larmour and Conway have stepped into the breach, leaving Schmidt excited by their freshness and form.
"I think that their enthusiasm is something that's contagious, their ability to get themselves into the game," said Schmidt, of Larmour and Conway.
"Andrew has proven aerial ability and that will be really useful for us.
"I still have the vision very clearly in my mind of Jordan Larmour beating Israel Folau to a ball in the third Test in Sydney on our Australian tour last year.
"So he's very good there as well, and of course Jacob is a big man in the back-field.
"They're all feeding off each other, they are all very, very keen to impress. And now they have that opportunity."
Assistant coach Andy Farrell declared both Kearney and Earls "available for selection" on Wednesday, but Ireland have opted not to risk either senior star in their pivotal Pool A battle.
Larmour's toughest task could be to stay strong under the high ball, the much-vaunted young star needing to hit top form to match one of Kearney's chief assets.
Schmidt explained that Ireland could have selected both Kearney and Earls, but prioritised instead picking players who had trained fully all week.
"Keith Earls was the sharpest player on Wednesday at training," said Schmidt.
"He was very, very sharp. He's good and Rob Kearney trained well as well.
"It was really just that we were getting tight for time. The best continuity we had was to have the guys we'd had training through the time we've been here.
"It's exciting to have the back three we've got as well. It's a great opportunity and a fantastic challenge."
Garry Ringrose has edged out Chris Farrell to start at outside centre, with Robbie Henshaw missing out due to hamstring trouble.
Ireland powered through a stellar 2018 boasting a Six Nations Grand Slam and a first-ever victory over New Zealand in Dublin in November.
Schmidt's men slipped to a third-place finish in this year's Six Nations, before suffering a record 57-15 defeat to England at Twickenham in August.
Back-to-back victories over Wales have helped Ireland edge back to form and top the world rankings for the first time though, and now Schmidt hopes he can wring the very best out of his squad.
Asked if Ireland are now ready to peak, Schmidt said: "You've just got to hope so, I can't guarantee anything, but in 48 hours' time we'll have a better idea.
"We'll be just arriving in the stadium and getting ready to warm up, I'll be anxious, and so will many others. Because you never quite know.
"But one thing I'll be really confident of is that we'll be tough to beat.
"That in 48 hours' time I think you'll see a very collective effort, and that effort will make us tough to beat. I've no doubt that the Scots will have been working away and will make themselves something similar.
"I don't think there's a huge amount between the two teams, so whoever does get the bounce of the ball or just be a little more efficient than the other just may tip the balance."
Renowned for concocting devastating set play moves, Schmidt admitted Ireland may roll out a few tricks that have been sat in reserve this weekend.
Asked if he still had a few tricks up his sleeve, Schmidt said: "These are short sleeves, so there's not too much up there!
"But there's certainly things that you do hold back a bit.
"We'll certainly see some things from Scotland that we haven't seen before.
"Because we've been planning this for a long time.
"And when you get the opportunity to put this into practice, it still has to be put into practice accurately.
"One of the things that is in the way of that is the amount of pressure the opposition can put on you and I've no doubt both teams will be trying to put pressure on each other so that whatever they have got planned isn't quite as effective as they'd hoped."
IRELAND TEAM TO FACE SCOTLAND IN YOKOHAMA ON SUNDAY: J Larmour (Leinster), A Conway (Munster), G Ringrose (Leinster), B Aki (Connacht), J Stockdale (Ulster), J Sexton (Leinster), C Murray (Munster), C Healy (Leinster), R Best (Ulster, capt), T Furlong, J Ryan (both Leinster), I Henderson (Ulster), P O'Mahony (Munster), J Van Der Flier (Leinster), CJ Stander (Munster). Replacements: N Scannell, D Kilcoyne (both Munster), A Porter (Leinster), T Beirne (Munster), J Conan, L McGrath (both Leinster), J Carty (Connacht), C Farrell (Munster).