PORT Adelaide coach Matthew Primus has apologised to the club's supporters following an "embarrassing" loss to newcomers Gold Coast at AAMI Stadium on Saturday afternoon.

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The home side started red-hot favourites against the winless Suns, who had lost their opening three games by an average margin of 93 points.

The Power looked like handing the visitors another hefty defeat when Daniel Motlop put them 40 points ahead late in the third quarter, but then the unthinkable happened.

The comeback wasn't quite as dramatic as Port Adelaide's 66-point turnaround against Adelaide in Showdown 30 last weekend, but it was equally unexpected.

Gold Coast kicked two late goals in the third quarter to cut the margin to 28 points at three-quarter time and continued on in the final term, piling on six goals to Port Adelaide's one to snatch an unlikely three-point victory.

After the game, Primus said the loss had damaged the reputation the club had been working tirelessly to improve.

"First of all, I'd like to apologise to our supporters for the effort that was produced today. We've got to delve real deep into the psyche of our club and understand why we produce these kinds of results," he said.

"It [the result] doesn’t do a great deal for the club. Our non-football staff have done an amazing amount of work for us along with our board to actually get some positive news behind the club, but we haven't held up our end of the bargain.

"It doesn't do wonders for the morale of the club and the brand. We have a brand that hasn't been well thought of for a couple of years now - we took a tiny step forward last week and have taken five steps back today."

Primus dropped experienced campaigners Kane Cornes and Danyle Pearce after disappointing losses to West Coast and Geelong earlier in the season and said he expected to make more changes ahead of the clash with North Melbourne next weekend.

"We want to be a good side, but we're a long way from that at the moment," he said.

"Credit to Gold Coast; they certainly wanted the game and believed in it for the whole period and that's what got them over the line. Kane and Pearcey are probably closer to selection [now].

"We've got to keep throwing around our 22 and finding out why we're not competitive week in and week out.

"It doesn't make for a good week, but that's the bed we've made and we've got to lie in it and do something about it."

Ruckman Dean Brogan was a late withdrawal from the team with an ankle complaint and Primus said the vice-captain was no certainty to play against the Kangaroos.