Andres Iniesta insists the Celtic Park atmosphere is among the best in the world and he was honoured to play there.
The Barcelona legend was part of the team who were beaten 2-1 by Celtic in 2012 when Tony Watt netted a late second.
Victor Wanyama had opened the scoring and Lionel Messi got a consolation in injury time.
It's one of Celtic's most famous European victories in recent times and Iniesta admits it's part of the reason he loves football so much.
The Hoops had very little of the ball with Barcelona dominating but Celtic defended brilliantly and Neil Lennon's men claimed the win.
In an interview with FourFourTwo, Iniesta was asked what the reaction was from players.
And he said: "I remember that well. One goal from a corner and another on the counter. Football is wonderful for reasons like these - the team who has the ball or the better players doesn’t always win.
"I’ll never forget playing against Celtic, either. The atmosphere is one of the best in the world. I was fortunate to play there several times and it was always so intense.
"It was an honour to play amid such incredible noise."
Iniesta was also asked to make a choice between Rangers boss Steven Gerrard, Paul Scholes or Frank Lampard.
But he stayed sitting on the fence and refused to put anyone ahead of the other.
He added: "That's difficult. Three brutal footballers. Three legends for their clubs, and three of the best players of all times.
"I have swapped shirts with all three of them. It means a lot to someone for whom football has been their life, and still is."
