Mark Williams ended his tenure as Port Adelaide coach a loser, with Collingwood defeating his AFL club by 26 points on Friday night.

The Magpies overturned a six-goal deficit to prevail 16.9 (105) to 12.7 (79) at a windswept AAMI Stadium.

Collingwood ball magnet Dane Swan was instrumental in the comeback victory, gathering a game-high 39 disposals, and Chris Dawes kicked three goals.

Port forward Brett Ebert kicked four majors, David Rodan and Steven Salopek were prolific ball winners, but Power players were unable to farewell Williams in style.

Williams earlier Friday announced he was quitting his post, the Collingwood fixture his last as coach.

He blew a kiss to his home crowd when leaving the arena at three-quarter time, but was ultimately helpless as Port fell to their eighth consecutive loss - an extension of an unwanted club record.

Williams, who had coached Port since 1999, was afforded a pre-game standing ovation from the 24,260 spectators before his side, kicking with a gale, blitzed Collingwood in the opening stanza.

Ebert was a constant threat with three goals as Port lodged 5.3 to Collingwood's solitary point by quarter time.

Collingwood's dismal opening was further marred by the report of Travis Cloke for striking, the Magpie forward felling Port onballer Travis Boak with a crude blow to the back of the head in an off the ball incident certain to have repercussions.

Collingwood opened their goal account in the second minute of the second term, only for Port to snatch two snapped goals against the wind, including Ebert's fourth, which established a 36 point buffer.

The goals against the gale appeared priceless, but the Magpies responded with a six goal rush in the next 20 minutes which squared scores at halftime, 7.5 apiece.

Collingwood midfielder Swan was the catalyst for the comeback, which also featured influential gems by the mercurial Didak.

Didak set up Swan for the first of six unanswered goals with a blink fast handball before posting two majors himself - the first an up and under snap from 40 metres which sailed on the breeze, the second a classy curled shot from a tight angle.

The Magpies then bunkered down in a game defining third term, mustering three goals into the wind which nullified Port's three, as the visitors took a one-point lead into the last quarter.

While the advantage was slender, the result appeared inevitable given the impact of the wind - only six goals were kicked against the solid southerly, and the Magpies duly sailed home to post their 11th win of the season.

Port has the task of appointing a caretaker coach for their trip to Darwin to face the Western Bulldogs next round, while the Magpies return home to prepare for a blockbuster against fellow flag aspirant St Kilda.

Williams briefly addressed his players and then promptly left without attending the post match media conference.

But Port's football operations manager Peter Rohde said Williams did not bow out "bitter and twisted".

"He went up in everyone's estimations ... he handled it as well as anyone ever has," Rohde said.

Collingwood coach Mick Malthouse said with Williams' departure announced the game had changed.

"Historically the game changes when those things happen," Malthouse said.

"What it does tell you is it's not played by robots ... it's played by the same human beings but with a different mindset and that is exactly what took place."

Brought to you by AAP © 2024 AAP