The anatomy of any injury scare in such an intense environment is always straightforward.
The player rests, does some physio and we all get down on our knees and pledge good deeds for the right outcome.
Naturally enough, Martin O'Neill is keen to avoid any major dramas but he has deadlines to meet which are irrevocable and that in itself adds to concerns about one of Ireland's main men, James McCarthy, or more precisely, on his backside.
It will be seated, hopefully comfortably, in the West Stand for Holland at the Aviva tonight.
An injury succinctly described by those who have experienced it as, quite literally, 'a pain in the arse', is a good bit more than a niggle and a good bit less than a screaming tale of woe.
O'Neill, in match mode and beginning to drift off into the place he goes when his mind begins to sift through the myriad of possibilities he must consider, told us that McCarthy travels, short of a disaster, whether he can get himself right for Belarus or not.
Usually in international combat, our only interest is the immediate opponent but now, a significant injury to a key player is relevant to four nations. Those in Ireland looking on watch for Italian injuries, Belgian bruises and yearn for Zlatan to trip over his ego.
Those viewing our patch from afar will see McCarthy as a big name in the Group E scheme of things.
O'Neill still sounds reasonably satisfied that whatever McCarthy's issue is, it is not something that would stop him giving his all three weeks from now against Sweden but as the Ireland boss said, he is a player who wants to play and he won't be against Holland tonight which has to be a worry.
"James McCarthy has done a little bit of training on his own and won't be playing. I'd like to give Ciaran Clark a few extra days as well," he said.
"I don't see that being a problem. James might be fit for Tuesday. If he doesn't play on Tuesday it might be a bit of a concern. He has played a lot of games for Everton. If it's a niggling injuries that needs a few extra days to get over, then so be it.
"If he doesn't play in any of the two games but feels that's all it is, I'd think James has done enough to be in the 23. He's been a major part of proceedings and that would be a situation that I would certainly look at and feel, well, if this is just an injury that needs extra time and he has played a lot of games, fine. Maybe those extra couple of days might do him a world of good.
"What I wouldn't like is to be going in with two or three players whose fitness has been a concern, not just for a day or two but over a period of time."
Players being players, nobody in green will be thinking too much about McCarthy when the game against Holland starts.
David McGoldrick, Harry Arter, Stephen Quinn, Darron Gibson and Eunan O'Kane are all pitching for a seat on the plane and they can be forgiven for selfish thoughts.
With Ciaran Clark also put on the easy list by O'Neill, even Paul McShane and Alex Pearce might be feeling a shiver of anticipation.
For O'Neill, the game is perhaps a final audition for the fringe and after that, Belarus will be about fitness though he claims the door will be open until the final whistle sounds at Turners Cross next Tuesday.
"As each day goes on, it's closing a little bit. But if it's down to that, a final time of saying, if I was a player and the manager was saying to me I had an opportunity tomorrow or Tuesday to be told that, regardless of how I did, I'd have a chance of getting in. I'd take that opportunity all day long. The players are happy to do so."
O'Neill's process of elimination will run through the weekend and he hopes to have narrowed his maybe list to a couple by the time it's over. It will be a difficult job which ultimately, he alone must do.
"I think if the players think they have an opportunity to get on the field and make an impression whether it's this game or Tuesday, I think they'd like to try this opportunity.
"I think I would naturally get a better idea when the game is being played. You're picking up things in training. I think a natural thing for players at the moment, they want to just impress. The best way to impress is do the things you're really good at.
"There are a number of positions (available). We can all pick 90% of the players and if you feel you're in that 10%, it's that time to impress as much as you possibly can but effectively.
"Somebody might just overwhelm us in these two games," he added, leaving the door wide open.