Craig Burley's weekend tirade at the commitment of his colleagues to the cause, including suggestions of players "hiding" in the treatment room, helped cure the club's malaise, according to Brattbakk.
The Norwegian front man might have considered himself partly implicated by Burley's additional complaint that as a midfielder he should be supplying rather than providing the bulk of Celtic goals.
But if he was hurt Brattbakk managed not to show it, instead insisting the club's ethos remains that it is good to talk, however painful it might be to hear what others really feel.
He said: "It would have been worse if Craig Burley had not said anything because that is part of being together in a team. I think you must feel you can say such things to or about each other without being offended. To my mind if Craig wants to express his views then he is perfectly entitled to do that."
Brattbakk came desperately close to proving his point with a goal against the Portuguese on Tuesday night, manufacturing a superb volley from a Tosh McKinlay cross that the visiting goalkeeper, Pedro Espinha, somehow tipped over the bar one-handed.
He grinned: "It does seem to me goalkeepers are playing better against me at the moment, it was a fine save from an equally good shot.
"I do feel perhaps it is now a case of one like that going in for me and the rest will come, but the most important thing is that the team are doing better and better.
"I know the more we improve and dominate games then I will get on the scoresheet. I feel it is going well again now so hopefully I can."
It was, for the most part, an assured Celtic display against Guimaraes, and certainly a marked improvement on recent home league showings, but there was still a needless late scare before clinching a second round spot.
Sven Soderstrom's speculative shot from distance cancelled out Alan Stubbs' 38th-minute header and it needed a last minute Henrik Larsson strike for victory on the night and a repeat scoreline as in Oporto a fortnight earlier.
Brattbakk added: "I was a bit frightened at 1-1 but we quickly got a good goal back and went through to the next round which was the aim. When we were 1-0 ahead it was 3-1 to us on aggregate which is always difficult because you know one goal and they are back in the tie.
"You need to balance defence and attack which is more difficult at home when the crowd expect you to play well and beat teams convincingly."
Brattbakk offered special praise to Larsson, who was the dominant figure over the two legs.
"Henrik is playing well, he just seems to find the right positions all the time and I'm not sure if I've ever seen him perform better," enthused Brattbakk.
"Wins always give teams confidence and especially in games such as last night's, but we realise we need to start securing victories in the league as well."Reuse content