Joe Schmidt will confirm his starting XV in the early hours of Thursday morning for Saturday's game against Japan.
The scheduling has thrown up one of the things that the head coach hates the most - the dreaded six-day turnaround.
"We've just got to accept it and manage our squad as best we can. It’s a frustration for everyone," he said after the impressive win over Scotland.
"We say 'if this player doesn't play this week, he might play that week' and try and balance things up and a lot of it was dependent on [Sunday's] result because if we didn't manage to get the better of Scotland, we were under pressure and we were going to have to try to put together the most cohesive side that we probably could.
"We feel that we've got to make sure that we're very, very good on Saturday but at the same time, we do feel that we can bring in a few fresh people and not lose the kind of cohesion we've been trying to build since we got together in mid-to-late June."
With that, and injury concerns over Robbie Henshaw, Johnny Sexton, Bundee Aki and Peter O'Mahony, in mind the coach will make changes for the Shizuoka clash.
The victory over Scotland has afforded Schmidt some leeway as he builds towards a quarter-final clash, most likely against South Africa.
Possible Ireland XV
15 Rob Kearney - It's not that Jordan Larmour put a foot wrong against Scotland it’s that Kearney remains Ireland’s premier full-back. Every now and again we need a little reminder of the value of the Louth man’s experience and game sense. If fully fit is likely to start a World Cup quarter-final and has only played 113 minutes so far this season.
14 Keith Earls – Another man short on game time and with competition hotting up could do with a lengthy run-out. Joe Schmidt is unlikely to get sentimental at this stage and a solid 80 minutes would convince the boss that his tendonitis and quad injuries are fully healed.
13 Garry Ringrose – With Robbie Henshaw central to Schmidt’s longer-term plans the Athlone back is unlikely to be risked on Saturday. Ringrose had a solid game on his return to the starting line-up in his preferred position.
12 Chris Farrell – Bundee Aki has gotten a clean bill of health following a HIA but the six-day turnaround might still be too tight for a game that Ireland go into as heavy favourites. Schmidt also mentioned that Earls and Larmour can cover the centre if necessary so rushing Aki back is not necessary.
11 Jacob Stockdale – Excellent in defence on Sunday this is the kind of match that he would relish give the space that may become available, Ireland have scored 12 tries in their last two games against Japan.
10 Joey Carbery – Coming this far and risking Johnny Sexton, who twice received on-field treatment against the Scots ('bang on the quad’) and declined goal-kicking duties after 16 minutes, would be unSchmidt-like. The Munster out-half needs to get game time under his belt, having played 49 minutes this season – that coming six weeks ago against Italy.
9 Conor Murray – No need to get carried away in terms of wrapping important players up in cotton wool. The Lions number nine was imperious against Scotland and, without Sexton in tow, should start against Japan.
1 Cian Healy – The prop admits he faces stiff competition from Dave Kilcoyne but is still Ireland’s number one loosehead. Japan will not go quietly into the night and the front five will be vital to subduing their efforts.
2 Niall Scannell – Captain Rory Best put in a savage 80 minutes on the weekend and deserves a rest. The Munster hooker could get a shot.
3 Tadhg Furlong – Another who produced the goods against Scotland and another similar showing for 50 minutes would go a long way to helping Ireland claim the win.
4 Iain Henderson – Forming a wonderful partnership with James Ryan and this would be another opportunity to hone his line-out calling.
5 James Ryan – Now equal to Sexton in terms of overall importance to Ireland’s hopes, Ryan, at 23, should relish these games.
6 Rhys Ruddock – Schmidt will be reluctant to risk Peter O’Mahony and you can easily imagine the coach reeling off the line, ‘if the game had been another day later, or a quarter-final he could have played’. Ruddock wasn’t in the squad last weekend so should be fresh.
7 Josh van der Flier – Replaced for a HIA by the impressive Jack Conan early on the flanker returned to play and was outstanding, deserves to keep his place
8 CJ Stander – Man of the match against Scotland, the South African looked close to his best and his rampaging runs can put Ireland on the front foot against Japan.
Replacements: Sean Cronin, Dave Kilcoyne, Andrew Porter, Tadhg Beirne, Jack Conan, Luke McGrath, Jack Carty, Jordan Larmour.
Listen to the RTÉ Rugby podcast on Apple Podcasts, Soundcloud, Spotify or wherever you get your podcasts.
Follow Ireland v Japan on Saturday (kick-off 8.15am) via the live blog on RTÉ.ie/Sport andthe NewsNowApp, watch live on RTÉ2 from 7.30am or listen to live match commentary on RTÉ Radio 1.
