WEST COAST has claimed its biggest scalp of the season and stamped its top-four credentials, downing an in-form Richmond by 20 points on a cold Friday night at the MCG.

Led by Nic Naitanui's total domination of the ruck, West Coast surged to a 13.12 (90) to 10.10 (70) victory on the back of a five-goal-to-two third quarter, snapping the Tigers' four-game winning streak in impressive fashion after coming into the match off consecutive six-day breaks.

It was a rare triumph for West Coast (9-3) at the home of football, only their fifth in 18 games since the 2006 Grand Final and first against an opponent other than Melbourne since 2007.

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The Eagles’ eighth win in their past nine games lifted them to second on the ladder, while Richmond's climb has been halted, the Tigers (6-5) sliding a spot to eighth.

Five talking points: Richmond v West Coast 

A hard-working midfield and stifling zone defence got the job done for West Coast, which slowed the Tigers' ball movement and restricted their three tall forwards.

Jack Riewoldt, Ty Vickery and Ben Griffiths combined for four majors and hauled in 13 marks, but West Coast's defence more than held its own.

"They're doing some unbelievable stuff behind the ball," Tigers coach Damien Hardwick said.

"Their zoning behind the ball is as good as we've seen this year, and we struggled to get through at times."

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Coleman Medal leader Josh Kennedy bagged three goals for West Coast, with Mark LeCras, Jamie Cripps, Jack Darling and Naitanui chipping in two apiece.

Emerging star Jeremy McGovern shrugged off concerns over a corked thigh to play an influential role down back, while improving onballers Andrew Gaff (31 possessions) and Chris Masten (25) combined brilliantly with midfield conductor Matt Priddis (27).

Dustin Martin tried to inspire Richmond with three first half goals, including an audacious checkside snap from 50 metres, but he, Brandon Ellis, Bachar Houli and Brett Deledio had too little help.

The match followed a familiar trend in every term, with the Eagles bursting out of the blocks before Richmond tried to reel the visitors in.

"It seemed to be there for a while two goals for us, two goals for them," Eagles coach Adam Simpson said.

"It was a little bit of a game of momentum there for a while; we lost it towards the end of the first quarter and we lost it towards the end of the second quarter. 

"I wasn't panicking, but I was concerned about how the game was trending."

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But playing catch-up football proved too big an ask for the Tigers, who were off the boil early coming off the bye.

Naitanui's (33 hit-outs, 12 disposals) brilliant ruckwork helped West Coast dominate the opening stages, with the Eagles winning the first nine clearances and racing to a 14-point lead.

So conscious were the Tigers of the 201cm Eagle that Troy Chaplin conceded a free kick for shepherding at a stoppage, then gave away a 50 metre penalty for abusing the umpire.

The incident handed Naitanui his second goal and is certain to spark further debate about the controversial third-man up rule.

WATCH: Nic Nat's electric ruck work

Martin (31 disposals) ignited Richmond when he intercepted a shocking turnover from McGovern to kick the first of his two opening-term goals.

The Tigers gradually got the contest back on an even keel and only trailed by a point at quarter-time.

Despite West Coast controlling play in the second term, they couldn't take full toll on the scoreboard.

Darling threatened to get off the leash, however Richmond finished the half strongest with late goals to Martin, Vickery and Trent Cotchin against the run of play to take a three-point lead into the long break.

But the Tigers struggled for fluency in the second half and only booted two more goals for the match, none in the final quarter.

Richmond now has to regroup for a crunch clash with the Sydney Swans at the SCG next Friday night, while Eagles head to the bye with a clash against Melbourne in Darwin to come.

Nic Naitanui was in formidable form as the Eagles ended Richmond's run. Picture: AFL Media

RICHMOND      4.2    8.3   10.6   10.10 (70)
WEST COAST  4.3   7.6   12.8   13.12 (90) 

GOALS
Richmond: Martin 3, Vickery 2, Griffiths, Miles, Cotchin, Deledio, Riewoldt
West Coast: Kennedy 3, Naitanui 2, Cripps 2, LeCras 2, Darling 2, Sheed, Yeo

BEST 
Richmond: Martin, Ellis, Deledio, Miles, Houli
West Coast: Naitanui, Gaff, McGovern, Yeo, Masten, Ellis, Priddis

INJURIES 
Richmond: C. Ellis (groin)
West Coast: Schofield (glute), Cripps (corked right thigh)

SUBSTITUTES
Richmond: Corey Ellis replaced by Connor Menadue in the second quarter
West Coast: Jamie Cripps replaced by Liam Duggan in the final quarter

Reports: Nil

Umpires: Dalgleish, Shaun Ryan, Ben Ryan

Official crowd: 45,178 at the MCG