Steven Naismith has warned the Republic of Ireland their hopes of reaching Euro 2016 will be left hanging by a thread if they fail to beat his Scotland side on Saturday.
Martin O'Neill's team trail the Dark Blues by two points going into this weekend's crucical Group D clash in Dublin.
Defeat to Gordon Strachan's men would leave them at least six points behind group leaders Poland - who take on Georgia - five behind the Scots and possibly just as many behind Germany, so long as the world champions see off minnows Gibraltar.
And Naismith has warned that will be difficult to overcome with just four games to play in the race to reach the finals in France next summer.
The Everton forward said: "If Ireland lose this it would put them at a disadvantage but I wouldn't say they'd be totally out of it.
"They would still have a big part to play in terms of facing the other teams and if they put a run of wins together they would still have a chance.
"But to be honest I'm not really bothered about what Ireland are doing, it's more about what we have to do."
While Scotland will hope to knock the Irish out of the qualification battle, they know failure to pick up all three points at the Aviva Stadium will allow Poland - who top the group with a one-point advantage over both Germany and the Scots - and Joachim Low's side to move clear.
But Naismith is refusing to worry about results elsewhere.
The former Rangers attacker - who came through a clash with Qatar goalkeeper Amine Lecomte in Friday night's 1-0 Easter Road win with only a scratch - said: "I don't think winning this game is more crucial with Germany and Poland expected to beat Gibraltar and Georgia, because when the next round of fixtures comes round and we play one of the so-called smaller teams, people will expect us to win.
"I think we just need to focus on this game and the position we are in.
"I've said all along that if you win your home games and put in good performances, you'll take points from the away ones and have a great chance of qualifying. That's what we've got to concentrate on.
"We felt we deserved our win in the first game against Ireland back in November and I'm sure we'll watch over clips of them over the next few days to devise a game plan to hopefully win again.
"There is an optimism more than ever in the squad. That comes from the competition for places in the squad being much higher and with results picking up.
"Over the last two years, even when our performances haven't been at our best, we've taken positives from the games and that helps to build the confidence as well.
"Also, a lot of the players are coming to the key part of their careers so they want to be going to these big tournaments instead of watching them
"Winning that last game at Celtic Park gives us confidence without a doubt. I think that was the big game a lot of people looked forward to with it being so close to home.
"The build up and the feeling before it had the sense of being a real big match so as the week rolls on I think it will be similar again. But I've said all along that we are confident in every game we go into."