Jim McGuinness may have won the All-Ireland with Donegal in 2012, but it is the semi-final victory over Dublin in 2014 that has become regarded as his managerial masterpiece.
The Irish Times has serialised extracts from his new autobiography, in which he outlined how he and Donegal pulled it off, and became the only team to stop Jim Gavin's Dublin winning a trophy they were after.
The extracts have already broke the news that the Donegal players backed themselves to beat Dublin. And he has enlightened us a little as to why they were so convinced.
Even before the quarter-final against Armagh, which Donegal came perilously close to losing, McGuinness had Dublin on his mind.
After hours of video analysis, in which he paused the tape so often, it took him four hours to watch seventy minutes, McGuinness laid down a blueprint which was followed to the letter.
The night before the game, he wrote down his anticipated final scoreline on the blackboard - Donegal 3-16 Dublin 0-12.
It eventually finished up 3-14 to 0-17. To which, one can only respond - what went wrong?
At our last meeting, I wrote Donegal 3-16 Dublin 0-12 on the blackboard. That was the final score we were banking on. It actually ended 3-14 to 0-17. It wasn’t too far off the mark because Dublin did kick unbelievable points in the first five minutes of the game.
Read the article here.