Hawthorn have kept their AFL finals hopes alive and dented West Coast's premiership defence after upsetting the Eagles by 38 points at Optus Stadium.
The 16.9 (105) to 9.13 (67) win on Saturday night improved Hawthorn's record to 11-11, but they need Adelaide to beat the Bulldogs on Sunday to have a chance of snaring eighth spot.
West Coast are in equal fourth, but they could slip to fifth if Richmond beat Brisbane at the MCG on Sunday.
But if the Tigers lose, the Eagles will remain in fourth and earn the double chance in the finals.
The Hawks lost Tom Scully to a game-ending ankle injury in the opening moments of the second quarter, but it wasn't the ankle he broke last year.
Hawthorn booted six unanswered goals either side of three-quarter time to secure the win, which was their sixth triumph from their past eight games.
West Coast will at least regain star ruckman Nic Naitanui for the first week of the finals.
But if they do end up finishing fifth, it would mean they would need to win four straight finals - three of which would be away from home - if they are to defend their premiership.
"It was a missed opportunity. Across the board I suppose the basics was where we fell down," Eagles coach Adam Simpson said.
"We've got some work to do, but we're still alive."
Hawthorn coach Alastair Clarkson was proud of his team's effort, and hopes Adelaide can do his side a favour in Sunday's game in Ballarat.
"What they do in the country, they ring up the opposition and offer them a barrel or something," Clarkson joked.
"I might have to put a barrel on for the Adelaide Crows boy to get up.
"But that (result) is out of our control. Irrespective of what happens, it's about the long game for us."
The Eagles dominated the clearances 45-29 for the match, but they lacked their usual marking prowess in defence.
Hawthorn forward Tim O'Brien booted four goals in a career-best display, while Shaun Burgoyne and Luke Breust chipped in with three each, and Chad Wingard starred through the midfield.
Andrew Gaff tallied 37 disposals and seven clearances for West Coast and Willie Rioli (15 possessions, three goals) was influential, but West Coast were uncharacteristically error riddled.
Hawthorn booted the opening three goals of the match to stun the 55,859 crowd.
But four goals in the space of three minutes saw the momentum flip, with the Eagles entering the first break with a six-point lead.
Simple errors hurt West Coast in the second term as Hawthorn piled on five goals to one to take a 16-point lead into the long break.
Hawthorn managed to hold off West Coast in a hard-fought third term, before opening up a 39-point lead early in the final quarter.
Eagles goalsneak Liam Ryan had the chance to close the margin to 21 points with 11 minutes to go in the match, but he hit the post from five metres out on the run.
Australian Associated Press