Sammy Clingan and Aaron Hughes have both discussed how fragile their international places can be, despite their top division quality and experience.
Clingan, who may be banging in the goals at Kilmarnock and recovering from injury as quickly as if he's still in his teens, suffered from being overlooked by manager Michael O'Neill while he drifted to the start of the 2012/13 season without a club.
Hughes, meanwhile, has only made five appearances for Fulham this season.
"We just have to keep performing at our clubs," said Clingan.
"This period now can be worrying, it can be a bit of a concern. Knowing there's another few months to wait is harder to take, I think.
"At the time it was really hard for me when I didn't have a club and I was missing international games, but now I am back playing and Michael has always kept to his word. I spoke to him a few times when I didn't have a club and he said I need to get back playing and when I do I will be back in the international set-up, so I am really thankful to him for that.
"I am really pleased with my last two performances so hopefully I can stay in the set-up.
"I know what's expected of me between now and February or March, whenever we meet up. It was totally understandable, what Michael was saying – I didn't have a club so I wasn't in, and he's done that to a few other players as well like Chris Baird and Paddy McCourt, but it was important to me that I got a new club and started playing again, so thankfully that's what has happened."
Hughes, who was persuaded out of international retirement by O'Neill almost two years ago, admits his club career has cooled lately, not least thanks to a troublesome thigh injury, but he plans on being available for international duty for as long as possible.
He said: "It might only feel like I am just back but I've been back for close to two years, and I wasn't just going to come back, have one campaign and call it a day – I was always going to come back and see how it went, so that's what I am doing.
"I very much want to be part of it going forward.
"I am grateful to international football, it's been nice to get away and have 90 minutes to be honest. That isn't the reason for coming out, I've come away to be part of the team but in that respect it was good to get out.
"Injuries are always frustrating for anyone and I've been extra frustrated, it kept me out of a couple of bigger games for Northern Ireland but I am well over it now, and have been back in training for two, three weeks.
"Like I said, it's good to get 90 minutes for me.
"For a few of us, I guess, who aren't really playing regularly at the minute it's just a case of trying to keep fit. We all want to be in the first team at our respective clubs and if that's not the case we just have to try and keep ourselves fit and come back. I am guessing February will be the next international, and Michael will use us as he sees fit.
"It's not as long as some people think. Christmas is a busy period and there are so many games it comes and goes quickly."