Robbie Neilson is convinced Hearts would have drawn 0-0 with Celtic had they not had over 5,000 fans there.
As it was, goals from Gary Mackay-Steven and John Souttar either side of Anthony Ralston's equaliser gave the Jambos a massive win on their return to the Premiership.
The early strike got the fans fired up although as they watched their team surrender possession and territory and Celtic level, things were in danger of going a bit flat.
But Hearts lifted it for the final 15 minutes and got a response for those on the sidelines.
And that was rewarded with a dramatic later winner from Souttar, which Neilson didn't think would have happened in front of empty seats.
"We had five-and0a0half thousand fans in here...it felt like 20,000," said Neilson.
"For them to come along and see that - it's been a long time since people have been at a live game - and to send them home happy is great.
"I think if this was last season with no fans in, that would probably have finished 0-0, having watched a lot of games and been involved in them.
"But when the fans start putting the energy back n the pitch, especially towards the end of the game, the team starts pushing. They find that extra yard, they start being more aggressive, pressed, made runs and gave us the goal.
"Yes the players scored it, but the fans pushed us which was brilliant to feel."
Neilson handed new signing Beni Baningime a debut and was delighted with what he got from the former Everton midfielder, even if he didn't expect him to last the 90 minutes.
"He was excellent," Neilson said. "He lasted longer than I thought he would. He's not played a lot of football but he did exactly what we wanted him to do. He broke up play, made tackles and as he gets fit, we'll get even more of him.
"In possession he was excellent as well so I'm really pleased with him."
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