Apart from a bad result in an important game, it's the one issue which could drive Mick McCarthy around the bend.
That's the constant debate and discussion about the players who are not in his squad as Ireland manager.
McCarthy was in Dublin yesterday, on another promotional gig for his employers in the FAI.
He was a busy man as he fairly wielded his axe, cutting 15 names from the 38-strong provisional squad, with Cyrus Christie the stand-out omission, a real drop for a man who was Ireland's Young Player of the Year 12 months ago and as clear a sign as possible that the Martin O'Neill era is over.
Another absentee was Stephen Ward, the 33-year-old informing McCarthy yesterday that he had joined the likes of Wes Hoolahan, John O'Shea and Daryl Murphy in retiring from international football.
McCarthy admits that his £100,000 purchase of Ward from Bohemians, when he was Wolves manager, was one of his best-ever buys and while the Ireland boss wanted to have Ward around in his squad, the Burnley player leaves with good wishes from his boss and his head held high.
But there was little warmth in the direction of two other players, the names of Declan Rice and Patrick Bamford cropping up. Again. To the manager's frustration.
Bamford, eligible for Ireland once he agrees to a switch from England and processes his paperwork, remains lukewarm about being one of the boys in green, telling McCarthy that he wants to focus on his career with a promotion-chasing Leeds United.
McCarthy, who as a player skipped the honour of being best man at his brother's wedding so he could play for Ireland in a friendly (against Poland), is likely to take the hint and give up on the player who is talented but is clearly not to fussed about playing for Ireland.
But McCarthy's anger over the Rice situation was evident when he was pressed for his views on the decision to name the West Ham man as Ireland's Young Player of the Year for 2018.
McCarthy requested that the panel of journalists reverse their decision to give the award to Rice, the Ireland boss yesterday telling a group of daily newspaper reporters that they needed to examine their role in the saga.
"You guys insisted that he be given it so I think that you should all have a look at yourselves, or whoever decided that," he said.
"Because when I was told that he was getting it, I said 'no way, why would he get it?'
"What I did say was that you give it to someone who appreciated it. And in doing so, everyone looks stupid. You guys - whoever it is - insisted that the integrity of the vote was maintained and that he got it .
"For someone who has left and does not even want to play for us, why in earth would you consider doing it? Was it to embarrass him, embarrass the FAI? I don't see the reason for doing it."
A score settled with the media, McCarthy also took an axe too his provisional squad, ditching 15 names.
James McCarthy, without a game for club or country in 14 months, has conceded defeat in his fitness battle.
Stalwarts like Aiden McGeady and David Meyler were left out, as were players who came through under Martin O'Neill (Scott Hogan, Shaun and Derrick Williams, Aiden O'Brien, Daryl Horgan) and Padraig Amond also failed to make the cut but Luton's James Collins is in while Josh Cullen could get a late call.
Alan Browne and Ronan Curtis were included but McCarthy does not expect them to be available, Curtis suffering the pain of a finger amputation earlier this week, the result of an accident at his Portsmouth home when his finger got caught in a door.
"He's had it amputated 80 percent, they said. I just felt really bad for him because he's had a great season," said McCarthy.
McCarthy had named veteran Ward in his provisional squad but the Burnley player later contacted the Ireland boss to inform him of his decision to quit. "I have spoken to him today and he is finished. He has told me he's retired from international football," McCarthy said.
"I wasn't expecting it. I think he was surprised and pleased that he had been named in the squad, I guess he shouldn't have been, knowing it was me, so I wasn't pre-empting anything, I put him in the squad knowing that if I needed Wardy he would turn up."
McCarthy signed Ward from Bohemians and he admits that with that deal and the bargain-basement purchase of Matt Doherty from the same club, for a combined fee of around €250,000, he had done well in his dealings with the Phibsboro club: "What was it from Bohs, £100,000? I think we'd both think that it was a success, and the Doc has done particularly well too."