Ben Presley Keough, 17, was snapped after he popped into Glasgow's Brazen Head pub after watching the Hoops in action at Parkhead.
And with the Bhoys winning, the youngster - who looks just like his legendary grandad - was delighted that there would be no Crying In The Chapel.
Ben, whose mum is Elvis's only child Lisa Marie Presley, 41, was taken to the famous Gorbals boozer by Gianni Capaldi, 34.
The businessman, from Hamilton, owns a string of LA nightclubs frequented by stars such as Justin Timberlake and Kirsten Dunst.
And he also took US singer Ryan Cabrera, 27, to the Glasgow boozer for some ALEHOUSE Rock.
Gianni said: "Ryan and Ben both enjoyed themselves in Scotland and I thought I would give them a cultural experience.
"So I took them to the Brazen Head pub in the Gorbals."
He added: "I think it was a bit of an eye-opener for them!"
Gian Fraioli, 37, who took our picture, said: "No one really believed that the King's grandson was in the building.
"But a couple of the bar staff went online and saw a picture of him, so that's how we knew.
"He had a brilliant time and got on well with everyone."
Ben's dad is Lisa Marie's first hubby, musician Danny Keough, 45 - who is a big Celtic fan.
Gianni added: "It's great that Ben has followed the tradition.
"It was his first trip to Scotland and first visit to Parkhead, so he was delighted. And he now knows the Brazen Head is the place to celebrate a Hoops win."
Last month Ben, who is also a singer, partied at a London nightclub with his mum and GRAN, Priscilla Presley, 63.
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