Martin O'Neill felt a "real Celtic Park atmosphere" had an impact on his side’s win over St Mirren after the return of the Green Brigade.
The ultras group had their ban lifted and the standing section was back at full capacity for the first time in about six months.
They were behind the team throughout the game, although some criticism of the board was reserved for after the game, with a banner branding them "unfit for purpose".
O’Neill felt the improved vocal backing helped his side through some difficult moments in their 1-0 victory over the Buddies, which kept them three points behind William Hill Premiership leaders Hearts.
Alex Oxlade-Chamberlain netted in the 15th minute but the champions could not build on their promising start and St Mirren competed well in the second half.
O’Neill said: "I thought the crowd were great to us, because they could easily have got irritated with some of the things we did.
"We were loose in possession at times, but they kept us going – a bit like against Dundee last weekend, which had a big effect on us staying in the game after Dundee had equalised. I thought they were great.
"If, by the end of the season, we could get a few things rectified, cleared up, call it what you will…
"But it felt like a real Celtic Park atmosphere."
St Mirren interim manager Craig McLeish admitted the atmosphere played a part and is looking forward to facing Celtic again next Sunday in the Scottish Gas Scottish Cup semi-finals with a far bigger Buddies support at Hampden.
"There are bits we need to keep working on for next week, and being brave from the very start," he said.
"I can’t ask for any more from the boys as to how they went about it in the second half, but we just have to find that final ball in the final third.
"We will have to make changes to some of our approach and I would imagine Celtic will be the same. It’s a one-off game, and the biggest bit for us is that we will have our fans in supporting us, and driving us on.
"Coming here, it’s so noisy and lively that you have to try and stem that flow, slow it down, and frustrate them. We have to be brave from the very start of the game."
McLeish, whose side remain in the thick of the battle to avoid a relegation play-off place, added: "We can’t be scared of it, we can’t have any fear.
"We can’t come to places like here and have any fear, we can’t go to Hampden with any fear, and we can’t play against any of the bottom six teams with any fear."
