Glenavon boss Gary Hamilton saw red after referee Andrew Davey dismissed Portadown captain Keith O'Hara - "and stopped the move that would have given us a point we deserved".
Hamilton insisted that the whistler should have played an advantage and his anger was justified when substitute Andy McGrory planted the ball in the net seconds after a shoulder-high tackle by O'Hara floored Ciaran Martyn.
"I can't for the life of me understand why the ref didn't play the advantage," said Hamilton. "If that goal had stood, we'd have forced a draw. We thoroughly deserved something from the game. The ref should have allowed play to flow and then dealt with the foul. We had wretched luck and I believe we were denied a couple of cast-iron penalty claims."
But as the victorious Ports trudged off, with the scalp of their great Co Armagh derby adversaries under their belts, an even bigger cheer erupted from the home stand when the matchday announcer relayed that Cliftonville had collapsed 4-1 at Seaview, "Portadown, Portadown top of the league," they chirruped.
It was a rip-roaring climax to a game where both teams gave all they had - the most action-packed Mid-Ulster derby in years and one which neither side deserved to lose.
Ports boss Ronnie McFall said: "I thought we just about edged it. They're a big strong side, but we had that little bit extra."
And on the fact it pops the Ports back to the top of the table on goal difference, McFall added: "It means little. Just two points separate the top four, with others in hot pursuit. It's a hectic race and it'll stay that way. Take a look at the table and see how tight it is - any one of six could take the title.
"This was a cracking match and I pay tribute to Glenavon as well as ourselves. Neither side could have given more. It was 90 minutes of non-stop commitment - a real thriller, a great advert for Irish League football."
It was all-go from the start, but the Ports drew first blood on 25 minutes when a Gary Twigg header struck the bar, and James Singleton committed a foul on the striker when trying to clear. Chris Casement crashed a cracker home from the penalty spot, giving keeper Alan Blayney no chance.
The Ports' second, on 37 minutes, was aided and abetted by Blayney who spilled a speculative Twigg effort, it found its way to Sean Mackle and the midfielder dinked it home from a few yards.
Glenavon pulled one back just before the break when a smart move up the left climaxed with a Neill cross, which was headed on by Martyn and Rhys Marshall bundled it home from close in.
Portadown restored their two-goal advantage on 49 minutes with Blayney culpable again - he failed to deal with a Ross Redman corner, and after Marshall cleared it off the line, Mark McAllister was on hand to make it 3-1.
Glenavon answered on 72 minutes when Eoin Bradley scored the goal of the match. His 22-yard stunner of a daisy-cutter foxed Miskelly and set up a grandstand finish with that 'red' incident giving it a rather spicy ending.
PORTADOWN: Miskelly, Casement, Redman, O'Hara, Breen, McMahon, Mackle, McAllister, Mouncey, Twigg, Garrett. Substitutions: Ramsey (Twigg, 89 mins).
GLENAVON: Blayney, McKeown, Neill, Murphy, Bradley, Dillon, Caldwell, Marshall, Braniff, Martyn, Singleton. Substitutions: Hamilton (Singleton, 73 mins), McGrory (Marshall, 73 mins).
Man of the match: Mark McAllister
Match rating: 8/10
Referee: Andrew Davey (Bangor)