The straight-talking Glenties man said when his team went three points ahead of The Dubs, he believed they had a date with Kerry.
“When we went 6-3 up I thought we could have done it if we had pushed on.
“But it wasn’t to be and Dublin knuckled down and continued to chip away with the scores. That’s just football.
“But yes I thought we could have done it at that stage. It was there for us but in fairness to Dublin they began to wear us down,” he said.
The loss of Karl Lacey was a huge blow to Donegal while the sending off of Diarmuid Connolly after 57 minutes seemed to spur Dublin on.
Donegal were still a point ahead but three unanswered scores form the Dubs brought the wheels of the Donegal trolley.
McGuinness and his panel are now expected to take a well-earned break but the manager is already talking about a new squad.
“We will sit down and evaluate the squad and take things from there.
“We have had a long hard season and every one of those players have given it their all. I could not have asked any more of them,” he said.