James Horan felt Donegal's performance in their Ulster quarter-final victory over Derry on Saturday evening was "classic Jim McGuinness".
"There's really good footballers in Donegal," Horan told the Irish's Examiner's Gaelic Football Show podcast.
"Over the last number of years, there were some of them missing. Ryan McHugh was gone, there was a couple of the O'Donnells that didn't play.
"You just knew straight away when Jim went in there that there would be a unification of all parties, all available players would be back.
"I had a quick chat with Eamon McGee and we went through it. 2011, 2012, 2013 - Donegal were hard running, anticipated the breaking ball, ran ahead of the breaking ball.
"They had really crisp handpassing. Their handpassing is always in front and on the money. You take it facing the goal. You can step as you get it. That was back.
"Plus, if you come into their 45, it's like you get attacked. They are strong, aggressive, the tackling discipline is really good and they get turnovers for fun.
"The fundamentals of the game Jim McGuinness always played were absolutely there on view. They were full of running, full of physicality."
Horan said he did not believe Derry underestimated Donegal, "but they certainly hadn't the focus that they've had in previous games".
"I know this sounds crazy but it's absolutely ideal for them," Horan remarked about the defeat for Derry.
"If you look at where they are, they have four weeks away from the limelight, away from everything and everyone will be talking about Donegal and Jim McGuinness and the Dubs are flying, and where are Kerry? They have a period of time to work on somethings and come back fresh.
"I think Derry were off it. I think, as far as I know, they were away on holidays, given a couple of days off leading into that game, which he hasn't done all year.
"They are double Ulster champions and of course you want a provincial title but it hasn't done them any good, in one way, in the All-Ireland run-in in previous years. I'm just guessing.
"I think they thought they had enough to get through it but now that they haven't, there will be a very clear path. I think you'll see a rejuvenated Derry in a couple of weeks."