The man is still alive, thanks to the assistance of a Rangers-supporting doctor who was onboard the flight.
He is reportedly well enough to still watch the game.
A club insider told the Daily Record: “The man was kept conscious and he is okay, he’s still alive.
“But obviously he’s had a heart attack so it’s very serious and was a big scare for him and his family.
“Luckily there was another fan on the flight who’s a doctor.
“He rushed to help him and looked after him on the flight.
“It’s the best outcome everyone could have hoped for in the circumstances.
“Hopefully he is well enough to still catch the game and gets the result we are all hoping for.”
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