Celtic staff and players returned to a heroes welcome at the Parkhead stadium after the 1-1 draw with Dundee United at Tannadice on Wednesday night that saw the Hoops reclaim the championship from Rangers.
As supporters let off flares and fireworks, Postecoglou emerged with megaphone in hand in a throwback to former fan favourite Kieran Tierney, who did likewise to lead the Celtic fans in a chorus after a 5-0 win over Rangers in 2018.
“I just want to say thank you from the bottom of my heart for all the support you’ve given me, the players, and everyone else,” Postecoglou said to loud cheers from the crowd.
"We’ll enjoy tonight, then we’ll come back Saturday, and we’ll enjoy it again.
"Thanks very much, and see you all Saturday.”
Postecoglou was visibly emotional during his on-pitch interview with Sky Sports after securing the point that rubber-stamped the title.
"It's pretty special, mate. It's probably the first time this year I'm lost for words," said the visibly moved head coach.
"Just an enormous effort and I'm really proud of the players and staff, the supporters, everyone involved. No-one gave us much of a chance at the start of the year, so to do what they've done this year and achieve the ultimate is an unbelievable effort.
"It's massive. The fans had a tough year last year. Not just the fact we didn't win anything but they couldn't come and support their team. They've been right behind us from day one and I couldn't be happier. I'm just really proud of this group of players and staff. They've been unbelievable for me this year.
"I think our football has been outstanding but the character this team has shown to get through the last 31 games and rise to every challenge, I couldn't be more proud of them."