West Coast, now wallowing at 1-4, led by 41 points midway through the third term but again was hobbled by poor goalkicking in the 12.12 (84) to 10.19 (79) loss.
Five talking points: Port Adelaide v West Coast
Conversely, the Power is 5-0, second on the ladder and looking assured of a spot in the top eight after a comeback that began in the 20th minute of the third term on Saturday night with emerging star Chad Wingard.
Wingard's goal after a dashing run and kick from pacey midfielder Jake Neade sparked a fightback as the Power kicked eight of the last nine goals of the game.
Click here to vote for the best three Port Adelaide players from this game
Power coach Ken Hinkley said he had inherited a squad that refused to give up; a quality evident soon after his appointment at Alberton when he accompanied the team on a pre-season trip to the AIS training base in Milan.
"From the day I went to Milan with this group, I've seen it," Hinkley said.
"They're a young, combative, desperate group of young fellas.
"I've had a group that is just willing to give everything they've got and I've seen that in pre-season in some of the tasks we set them."
I thought we were gone, admits Hinkley
Wingard, Angus Monfries, captain Travis Boak and Hamish Hartlett each kicked two goals in the burst as West Coast struggled with just three players on the bench after the early substitution of Matt Priddis (concussion).
The key onballer had his arms pinned in a Monfries tackle just minutes into the match and crashed face first into the turf.
Worsfold said it was unknown whether the prolific ball-winner would be available to face the Western Bulldogs next weekend.
"It's not my decision [whether he plays], that all depends on the medical assesments," he said.
Boak's pair came within 90 seconds and gave Port the lead - for the first time in the game - 11 minutes into the last term.
Eagle Bradd Dalziell replied to restore a two-point break for the visitors.
Click here to vote for the best three West Coast players from this game
But Port recruit Monfries capped a spirited comeback, running into an open goal in the 19th minute and his side held on.
In the first term, West Coast kicked into a strong breeze but still managed its second-best first quarter of the season and a 22-point lead at quarter-time.
After kicking 7.23 against Carlton last week, West Coast was again plagued by the yips in the second term, with the exception of Josh Kennedy.
We can still win the flag, says Woosha
The elusive forward threaded four set shots, though teammates missed others as only inaccurate goal shooting - 7.13 - kept Port in it.
The Power mustered only 2.5 in its dismal opening half, despite Kane Cornes gathering 15 touches to half-time in his 250th game.
In a further blow, West Coast skipper Darren Glass was reported in the second term for a late shirtfront which stunned Port's Paul Stewart.
Port's losing fate appeared sealed when Chris Masten goaled in the third to give West Coast a 41-point advantage.
Eagles coach John Worsfold said his side became complacent after leading by such a margin late in the game.
"We stopped putting the pressure on Port that we'd been putting on, and let them start running," Worsfold said.
"We really just stopped the pressure game, I think."
But Wingard sparked the tremendous comeback as the Eagles slumped to their fourth loss in five starts this season and Port coach Ken Hinkley's flawless start to his coaching career continued.
Justin Westhoff fends off Scott Selwood on Saturday night. Photo: AFL Media
PORT ADELAIDE 1.0 2.5 7.7 12.12 (84)
WEST COAST 4.4 7.13 9.16 10.19 (79)
GOALS
Port Adelaide: Wingard, Boak, Monfries, Hartlett 2, Stewart, Neade, Broadbent, Cornes
West Coast: Kennedy 4, Cripps, Hill, Darling, Masten, Hams, Dalziell
BEST
Port Adelaide: Hartlett, Boak, Neade, Wingard, Cornes, O'Shea.
West Coast: Selwood, Shuey, Brown, Gaff, Kennedy, Cox.
INJURIES
Port Adelaide: Pittard (general soreness) replaced in selected side by Lewis Stevenson.
West Coast: Matthew Priddis (concussion)
SUBSTITUTES
Port Adelaide: Robbie Gray replaced Jackson Trengove in the third quarter.
West Coast: Jamie Cripps replaced Matthew Priddis in the first quarter.
Reports: Darren Glass by umpire Pannell for rough conduct against Port Adelaide's Paul Stewart in the second quarter.
Umpires: Fila, Kamolins, Pannell
Official crowd: 26,132 at AAMI Stadium
