The Pirates, who suffered a fifth defeat in six matches to leave them languishing in the npower League Two relegation zone, were stunned by three City goals in five minutes.
Garry Kenneth put through his own net to hand the hosts the advantage and although Tom Eaves hit back a minute later, the Minstermen soon responded through Ashley Chambers and Jason Walker.
Chambers' struck again 12 minutes before the break to seal the win and McGhee's fate. His 11-month spell at the club was brought to an end soon after the post-match press conference.
"I'm one down from embarrassed, I'm humiliated and that maybe is the right word to describe the first half," McGhee said, speaking before the decision to dismiss him was announced.
"I always question myself first and I will do that first, but I also have to question the teamwork in a sense and that comes back to me ultimately. Once the players cross that line they have to be prepared to give us more in the first half.
"The shape in the early parts of the game gave us problems but it came down to individual situations such as stopping a cross and these things kill you.
"It gave us far too much to do. You can talk all you want about the chances we had before they scored and after and they were terrific chances.
"Second half was much, much better. It wasn't about them dropping off, it was about us stepping up from the start and giving us much more to get at them and create chances.
"Some of the defending in the first half was terrible but we improved second half."
- Sports & Recreation
- Ashley Chambers
- Garry Kenneth