Celtic's run to the 2003 UEFA Cup final was a memorable journey but they fell just short against a Porto side managed by Jose Mourinho.
Porto would go one better the following season by winning a surprise Champions League trophy, but their European trips were full of incident.
The match with Celtic was quite heated between the sides in Seville and one flashpoint in the tunnel at half time involved Mourinho and ex-Celtic winger Alan Thompson and former defender Jackie McNamara.
They were on hand to tell us about it at our Off The Ball Roadshow at Vicar Street.
Indeed, Thompson played his parts in the tempestuous scenes following Derlei's goal and celebration for Porto, as he revealed.
"That got tempers fraying just before the whistle goes. Down the tunnel, there's a bit of a fracas in the tunnel and he's piped up, Mourinho," said Thompson.
"And I've got a Lucozade in my hand and I've just..."
Thompson grabbed a bottle on stage at Vicar Street then motioned as if to spray the area in front of him.
"Straight over Mourinho," he continued. "And then it's all kicked off. I sprayed the Lucozade in his face.
"And then it got even worse and more people piled in and I thought I'd better run!"
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