Alastair Clarkson might have done it again.

Three weeks after Hawthorn's season looked shot, the master coach could have snuck his side into September following a perfectly orchestrated 38-point upset of West Coast. 

For so long the Eagles' nemesis, Clarkson's Hawks might also have struck a hammer blow to the reigning premiers' top four bid, with their hopes now hinging on Brisbane upsetting Richmond. 

But Saturday night's spotlight should be on Hawthorn. This was an unforgettable victory.

At the end of round 20, the Hawks sat two wins and more than 10 per cent behind the Crows in eighth spot with just three games to go.

But after thumping wins over Gold Coast and the Giants, they produced a stunning 16.9 (105) to 9.13 (67) win at Optus Stadium and will enter the final day of the regular season occupying eighth spot. 

The Dogs, Crows and Power could still unseat them, but the challenge has been thrown down.

Meanwhile, if Richmond defeats Brisbane at the MCG, West Coast will be stuck in fifth and have to defy history to stand a chance of appearing on the last Saturday in September. 

In 20 seasons under the current top-eight system, no non-Victorian team has come from outside the top four to reach the Grand Final.

Even if the Eagles won a home elimination final, they would have to travel three consecutive weeks from Perth to clinch the premiership.

With former Eagles player and assistant Sam Mitchell by his side, Clarkson was the architect of West Coast's demise again, inspiring his troops to shut down the home side's ball movement. 

Hawthorn was tougher at the contest, tackled harder and was electrifying with the ball in hand, and couldn't have wished for a better start.

Before the Eagles had blinked, the Hawks drilled three goals and set the tone for a famous win.

Every time West Coast challenged, and it wasn't often, Hawthorn had an answer.

The Eagles hit the front by quarter-time after a four-goal surge, but when Jack Redden and Dom Sheed missed gettable shots the Hawks made them pay.

Five of the next six goals went the brown and gold side's way, with a Tom Barrass mistake down back and Luke Breust goal starting the landslide.

Knowing its season was on the line, West Coast squeezed the margin back within a kick early in the third term – after Jack Darling's second took his tally to a personal-best 54 majors. 

But Darling was outshone as the best forward on the ground by unsung Tim O'Brien, whose career-high four goals might be remembered as a watershed moment in his 62-game career.

O'Brien nailed three of his goals during a game-winning surge in the second half, when the Hawks piled on six unanswered to open up a 39-point break.

West Coast mounted something of a challenge with two quick goals, but when Liam Ryan ran in on an angle and cannoned his shot into the post their hopes of a remarkable comeback were dead and buried. 

The Hawks had winners everywhere, none better than Chad Wingard (28 disposals, 10 inside 50s), while evergreen Shaun Burgoyne (three goals) and Luke Breust (three) were enormous. 

Barely a West Coast player would walk off head held high, and they will wake on Sunday morning wondering where it all went wrong.

MEDICAL ROOM

West Coast: Half-back Brad Sheppard was hurt in a collision during the second quarter, seemingly struggling with sore ribs on the bench, but returned and played out the game. 

Hawthorn: Tom Scully came from the field midway through the second quarter with an ankle concern. He went down to the rooms and emerged soon after without his football boots and his night was done. 

NEXT UP
It's wait and see for West Coast. The Eagles will more than likely host an elimination final against Essendon or the Hawks, but have the slightest hope of travelling to face Brisbane or Geelong in a qualifying final. If Hawthorn stays in the eight, it will come back to Perth to face the Eagles in a cutthroat final.

WEST COAST 4.3 5.8 7.11 9.13 (67)

HAWTHORN 3.3 8.6 11.6 16.9 (105)

GOALS

West Coast: Rioli 3, Kennedy 2, Darling 2, Ryan 2

Hawthorn: O'Brien 4, Burgoyne 3, Breust 3, Gunston 2, Smith, Nash, Henderson, Sicily

BEST 

West Coast: Gaff, Rioli, Masten

Hawthorn: Wingard, O'Brien, Ceglar, Henderson, Worpel, O'Meara, Sicily

INJURIES 

West Coast: Nil

Hawthorn: Scully (ankle)

Reports: Nil

Umpires: Foot, Margetts, Dore

Official crowd: 55,859 at Optus Stadium