Pressure has intensified on Levein since Scotland lost 2-1 to Wales in Cardiff on Friday night, a game that Scotland desperately had to win to have any chance of keeping their Fifa World Cup qualification hopes alive.
Bottom of Group A now with just two points from three games, Scotland's task does not get any easier as they face up to group favourites, Belgium.
Asked if his position would be tenable were Scotland to come away from the game in Brussels with nothing, Levein bristled.
"I keep getting asked questions about 'what if this happens?' or 'what if that happens'?" he said. "I'm not prepared at all to enter into that.
"My job is to prepare the team for the game, they will be doing their absolute best as always and I've got every confidence in the players."
The pressure will only increase further if the Scots suffer yet another disappointment tonight night but Levein added: "I'm not worried about that at all.
"I'm concentrating completely on the match. Having my focus on anything else is counter-productive."
Levein was also asked if tonight's game is the biggest of his managerial career, simply because there is so much pressure on him going into it.
He said: "It seems that every one is the biggest one. It's a tough ask but I've got huge confidence in the players.
"They showed in long spells on Friday that they are capable.
"We harbour a sense of injustice and one thing is for certain, we will put on a good performance, I'm sure of that."
Levein is set to make just one change from the team that started the Welsh game. Wigan's James McArthur will come in for the injured Scott Brown.
Levein believes Scotland are capable of channeling their anger about Friday's game against Belgium.
"There is still a tinge of disappointment with the way the game turned out on Friday as you can imagine," he said.
"We feel we were badly let down by the officials and we have to use that anger to help us tomorrow night.
"In all my time in football I have never seen a decision like that so it's very difficult to take.
"Now it's about tomorrow night. This game is an opportunity for us to put Friday to bed."
"There is absolutely no doubt we have a big performance in us. We have seen that."
