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'll need Adelaide to beat the Bulldogs on Sunday to have a chance of snaring eighth spot.
West Coast slipped to fifth, and they will stay there if Richmond beat Brisbane at the MCG on Sunday.
But if the Tigers lose, the Eagles will move back up to 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.
West Coast led by six points at the time, but Hawthorn put in one of their bravest displays of the season to take down the defending premiers.
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.
The Eagles now face the unimaginable prospect of losing the double chance during the finals.
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 title.
Scully's ankle injury would be a concern to Hawthorn.
But the good news is he didn't injure the right ankle that he broke early last year.
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.
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 loose with possession.
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.
The most costly mistake belonged to Eagles defender Tom Barrass, whose dropped mark resulted in a goal to Luke Breust.
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