In 2006, Dublin and Mayo met in the All-Ireland semi-final at Croke Park.
When Dublin went to undertake their customary warm-up in front of Hill 16, they found the Mayo team already in place at that end of the ground.
As then Mayo footballer David Brady, former Dublin selector Paul Clarke and Dublin fan Cormac Farrell tell RTÉ Sport's Peter Sweeney, sparks flew...
"On the day we would have killed each other with our bare hands if we'd got the chance," smiles Brady.
"But that's football. What happens in the game stays in the game and sometimes what happens before the game is forgotten about as well."
Mayo went on to win the game by 1-16 to 2-12 before losing to Kerry in the final.
