Scotland sealed World Cup qualification with the 4-2 victory as Norwich City midfielder McLean struck from the halfway line.
Aston Villa capain McGinn said afterwards: "I've played with Kenny for years at St Mirren. To see that ball hit the net, I can't even explain.
"I thought we were pretty rubbish to be honest, but who cares?
"To get over the line was such an amazing feeling. The gaffer's team talk was exceptional. It's a privilege every time we meet up. It's just humble guys wanting to do well for their country. We left everything out there.
"I thought I'd blocked Dorgu's shot. You think that's it - glorious failure, another blow. I was thinking about the play-offs 91st minute.
"What a hit from KT - I will never feel like that in a football stadium ever again."