Gary Liggett moved into double figures for the season as Dungannon Swifts claimed another priceless point in their quest for survival.
The striker showed a clinical edge on a day of missed chances at Shamrock Park.
His first half header was his sixth in the league this term, with another four goals coming in the two main cup competitions.
Unfortunately it wasn’t enough to secure all three points, with Portadown hitting back in the second period through Chris Casement.
However, Casement’s afternoon ended in frustration when he and Robert Garrett were sent off in a bad-tempered finale.
The point was the least Dungannon deserved after another encouraging performance.
Darren Murphy’s side have lost just twice in the league since the turn of the year, and are now eight points above the drop zone.
Liggett felt they more than merited a point.
“I thought it was a good performance – particularly in the first half,” the forward said.
“In the first five minutes we were a bit edgy and Alvin Rouse pulled us out of a couple of holes, but after that we did really well.
“We went 1-0 ahead and thoroughly deserved it.”
Terry Fitzpatrick and Jamie Douglas spurned chances in either half, while the Ports could also reflect on a series of missed opportunities.
Liggett added: “We deserved at least a point and on another day could have won it.
“We can’t be too unhappy as we’d have taken a point before the game.”
It might have been different had Portadown scored from one of two terrific chances they created early on.
Both times Alvin Rouse produced terrific stops, turning Peter McMahon’s drive wide before blocking Casement’s strike at point-plank range.
Dungannon also went close early on via Fitzpatrick, who headed straight at the goalkeeper from a great position.
After that frenetic opening, the visitors grew in confidence.
Fitzpatrick took a pass from Matt Hazley and again aimed for goal, forcing David Miskelly to make a smart save.
They took the lead after 30 minutes. Ryan Harpur delivered a corner and Liggett beat two defenders in the six yard box to head home.
Portadown improved in the second half and levelled in the 63rd minute.
Dungannon failed to deal with a ball in their box, and it reached Casement who adjusted his body to score with a stunning right-foot strike.
Although Portadown’s early carelessness with the ball had gone, Swifts had the better chances in the closing stages.
Douglas twice went close, beginning with a first-time, left-foot strike which worried the goalkeeper but flashed narrowly wide.
He threatened again after being teed up by Liggett, only to fire over when it seemed easier to score.
The red mist descended in the final moments, starting with a red card for Garrett after he got in a tangle with Jamie Glackin.
Soon afterwards the assistant referee spotted an off-the-ball incident involving Casement, who was also sent from the pitch.
Portadown: Miskelly, Casement, Redman, Breen, Oman, McMahon, Gault, Garrett, Mouncey (McAllister, 46), Mackle, Twigg. Subs not used: Brennan, Ramsey, McElroy, Richardson
Swifts: Rouse, Burns, Brennan, Wilson, O’Rourke, Hazley (McCullough, 24), Harpur, Fitzpatrick, Glackin, Douglas (S Lavery, 84), Liggett. Not used: Armstrong, Mitchell, Sanusi
Keith Kennedy, Lisburn