Davis Keillor-Dunn climbed from the bench to net the decisive strike, latching onto a delightful Zak Rudden back-heel before coolly slotting beyond Ryan Scully to send the 800-strong travelling support into raptures.
Falkirk’s second successive 1-0 win at the home of their fierce foes this term saw McKinnon’s men climb off the foot of the table at Partick Thistle’s expense.
Just four points now separate five clubs at the bottom of the Championship ahead of what promises to be a blockbuster finale to the campaign.
“We were bottom of the league with no points for a portion of the season,” said McKinnon. “Now there are five teams in it, so we deserve credit for that. We are fighting tooth and nail and showing tremendous effort, energy and commitment. “
However, the Pars will wonder how they emerged empty-handed after dominating for large swathes of the contest. On-loan Aberdeen kid Bruce Anderson saw a first-half penalty saved by the superb Harry Burgoyne after he had been felled by Ciaran McKenna, while Dunfermline captain Lee Ashcroft headed against the woodwork.
McKenna also inadvertently chested the ball against his own post as Falkirk rode their luck in the dying embers.
“Dunfermline had a couple of great chances and we maybe carried a bit of luck,” added McKinnon. “But the boys deserve that.”
Pars boss Stevie Crawford added: “We created more than enough chances to win the game.”