The reputation of Ronny Deila's side took a battering when they crashed 6-1 on aggregate to Legia Warsaw in the third qualifying round.
The Polish club then attempted to drag Celtic's name through the mud as they sought to wriggle out of the punishment for fielding an ineligible player in the second leg of their tie.
There have even been calls for the Hoops to be booed whenever they appear in Europe.
But none of this will enter the minds of the players when they line up against NK Maribor tonight determined to make the most of their second chance and prove they are worth their place in the play-offs for a Group Stage place.
Fresh from his two goals against Dundee United at the weekend, Jo Inge Berget wants the chance to show Europe Celtic's true face.
He knows the Ljudski vrt stadium - part closed by Uefa after racist chanting - will be hostile, but said: "We have to shut out everything that has happened to get us here. We can't do anything else. We have got to just play this game.
"It's not like Celtic decided what was to happen. It was Uefa's decision.
He added: "We need to be professional about it … And, of course, we need to be better than we were against Legia."
Saturday's 6-1 win over Dundee United has put everyone in the right mood to deliver.
"The way we played and scoring a lot of goals gives us confidence going into this match," confirmed Berget, who got goals five and six.
He concedes he failed to fire on his debut for the club in Warsaw, and wants to change fans' first impressions
Deila is still confident he will be an important Hoops player, but on nights like this his faith must be justified by every player selected.
Berget added: "It's up to us to perform. The manager wants to play football and he wants to entertain. That's what we did against Dundee United.
We want to have aggression too, particularly in defence when we are pressing all the time."