When Joe Schmidt sat down with his backroom staff last week and decided on the final number of players that would travel to Portugal, the two main things he would have taken into consideration were fitness and game-time.
Tadhg Beirne, Andrew Conway and Jack Conan were the three unlucky ones to miss out through injury, while Schmidt felt it was best for Jack McGrath and Rob Kearney to get more minutes with Leinster before Saturday's Six Nations opener against England.
Neither McGrath nor Kearney are likely to have been best pleased with the Ireland head coach's decision that saw them miss out on a crucial week of warm-weather training in the plush surroundings of the Quinta do Lago resort.
What perhaps made the decision even more tough to stomach for the pair was the fact that Robbie Henshaw and Seán O'Brien, both of whom have far less game-time under their belts after lengthy periods out injured, travelled with the 35-man squad to the Algarve.
Kearney, in particular, has proven in the past that he can bounce back well from injuries. While he might have felt he needed a run-out at the RDS on Friday night, deep down it must have been difficult to get fully motivated to play against the Scarlets in such a low-key PRO14 fixture with what's to come over the next seven weeks.
The IRFU's player management programme is designed on a player-by-player basis, and the hour that Kearney played against the Welsh side won't exactly have filled Schmidt with much confidence leading into this weekend.
That said, write Kearney off at your peril. We have been down this road so many times in the past and yet Kearney invariably delivers the kind of performance that silences the doubters and reminds everyone just why he remains Ireland's first-choice full-back.
Rewind the clock back to late October when he suffered a chest injury playing for Leinster in another unglamorous PRO14 clash, this time in Treviso.
It subsequently cost him two weeks out, which saw Kearney miss the trip to Chicago that he was unlikely to have been selected for anyway and then the win over Argentina - a game he almost certainly would have started in, had he been fit.
A recall was on the cards a week later for Ireland's historic first home win over the All Blacks, in which Kearney was excellent.
Fast forward to last Friday night, and the Louth native would be the first to admit that it was not his finest hour as his rusty performance left more questions than answers.
Three poor, missed tackles will not have sat well with him or Schmidt, who is well aware that Kearney has plenty of credit in the bank.
"Rob has so much experience at the top level, he will come back in," Leinster head coach Leo Cullen said, offering his full backing to Kearney. "He is so comfortable in the air. He has so much experience, Rob. I wouldn't worry about that.
"He will be better for having come through game minutes because he's just been a little bit shy in that. He will be well able to step up."
There will be calls from the usual quarters for Kearney to be dropped for the Six Nations opener, yet having linked up with the squad last night, it would be a major surprise if he isn't selected to wear the number 15 jersey against England.
Some will continue to point to his attacking threat, but as Kearney told this newspaper in November: "I've been dealing with that my whole career and the last four or five years with supporters thinking this and that about me."
He might be on a barren 45-game run without a try for club or country, but as he has shown time and time again, Kearney brings so much more to both Leinster and Ireland.
An astute reader of the game, his communication is second to none, which doesn't grab the headlines in the same manner as other, more glamorous Irish back-three players have done in the last 12 months.
Before Ireland's win over the All Blacks in 2016, Schmidt told Kearney that he needed a big game from him in Chicago. He duly delivered.
Kearney has been in this position so many times over the years, and given how delivering under pressure has become second nature to him, don't be surprised to see him repay Schmidt's faith with another assured performance on Saturday when the stakes are high.