Dundee United enjoyed "probably the best feeling in football" as Kevin Holt's 94th-minute header at a sold-out Tannadice and moved them to within three points of third-place Scottish Premiership opponents Aberdeen.
In an open, high-tempo contest, Jack Walton and Dimitar Mitov both made excellent saves to protect their respective clean sheets in a captivating first half.
United's Walton showed excellent reflexes to palm away Ester Sokler's effort, while Aberdeen's Mitov kept out Glenn Middleton's low drive before getting up to claw away Kristijan Trapanovski's rebound header.
Trapanovski and the league's top scorer Sam Dalby both went close after the break, as the home side pushed for victory, and it eventually came in the 94th minute.
Will Ferry's long throw found Holt and the defender rose highest to find the bottom corner to send the home crowd into ecstasy.
"We send all the big boys up," Goodwin said. "A great throw-in from Will Ferry and unbelievable desire from Kevin Holt.
"Over the balance of play I think we deserved to win. The players managed the game brilliantly - defensively outstanding again.
"It's probably the best feeling in football when you get that last-minute winner."
The result moves United closer to Aberdeen and Rangers, who are now five in front ahead of the side's respective derbies on Thursday.
Jimmy Thelin's visitors, though, missed the chance to move above the Ibrox side and are now winless in eight as their wretched run continues.