AN UNDERSTRENGTH Greater Western Sydney has raided West Coast's fortress and defeated the Eagles for the first time with a heart-stopping eight-point win on Sunday.

In an unrelenting arm-wrestle where the lead changed eight times in a gripping final quarter, the Giants engineered one of the greatest wins in club history to move to an 8-2 record and keep pace with League leaders Adelaide.

Toby Greene was the hero for GWS, booting a booming set shot late in the fourth quarter before bouncing through a sensational major from outside 50m near the boundary to clinch a 14.14 (98) to 14.6 (90) victory.

Full match coverage and stats

Lewis Jetta (28 disposals) starred for the Eagles and the speedster stole his second major from the goalsquare from a loose Lachie Whitfield pass only minutes later, but he couldn't stop the home side suffering their first loss in Perth this season.

The Giants' maiden win over West Coast – in their sixth clash - means the expansion club has now beaten every other side, and came with nearly half their best 22 on the sidelines.

On the road and severely undermanned, GWS had to do it the hard way, coming back from 14 points down at quarter-time after West Coast piled on five-straight majors. 

Five talking points: West Coast v Greater Western Sydney

Led by behemoth Shane Mumford's (50 hit-outs) presence in the ruck and Dylan Shiel's (26 disposals, two goals) superb first half, the Giants commanded the clearances (53-32) and worked their way into a three-point lead at the final change.

GWS surrendered the advantage almost immediately when Josh Kennedy steered through his third major.

But the Eagles lost their spearhead to a leg injury from an innocuous incident only minutes later, and the Giants never lost their belief.

Every time West Coast hit the front GWS found an answer, and when Greene stepped up the visitors had enough in the tank to clinch their fourth single-figure triumph in five games.

"I thought (the win) was more on the back of persistence rather than maturity in close situations," Giants coach Leon Cameron said post-match. 

"(Greene) is a super player for our club and he wins his own ball.

"I thought that (Mumford) was terrific. I thought Mummy set the scene for us early and helped our clearance count throughout the day."

In-demand midfielder Josh Kelly (29 disposals, one goal) was inspirational for the Giants – especially in a huge third term – while skipper Callan Ward (33) steeled his side and half-back Nathan Wilson (20) sliced the Eagles open with his foot skills.

WATCH: Persistence pays off for Toby

West Coast key defender Jeremy McGovern (nine marks) kept Jon Patton quiet and dominated after half-time, while Andrew Gaff (34 possessions), Elliot Yeo (31), Sam Mitchell (31, one goal) and Dom Sheed (31) never stopped trying.

The Eagles sorely missed Luke Shuey – who was a late withdrawal with a calf issue – and slumped to 6-4, but missing personnel was no excuse given GWS' injury woes.

The Giants only had 26 fit players to choose from and lost Tom Scully (knee soreness) before the game, with the gut-runner joining the likes of Stephen Coniglio, Steve Johnson, Rory Lobb, Ryan Griffen and Devon Smith on the sidelines.

West Coast coach Adam Simpson couldn’t fault his side's intent – they almost squared contested ball 106-108 – but the Eagles were fighting an uphill battle after being dominated in clearances and inside 50s (56-43). 

"The intent and effort was there for the most part. There was some poor execution at stages, a bit of class got us at stages as well," he said.

"We're losing a lot of supply. Our field position at the moment, we're doing a lot of our rebounding from the back half.

"To lose the clearances by (21) and win contested possession … there were some good signs there I thought." 

MEDICAL ROOM
West Coast: The Eagles will have to rejig their forward setup in the wake of a suspected calf injury suffered by spearhead Josh Kennedy, the severity of which won't be known until after scans. Luke Shuey (calf) and Mark LeCras (hip) are chances to be available to face Gold Coast. 

Greater Western Sydney: The Giants emerged from the match unscathed. Tom Scully (knee soreness) was close to playing the Eagles but was withdrawn pre-game and should be back next round.  

NEXT UP
The Giants are looking ominous despite their injuries and return home to host Essendon at Spotless Stadium, while the Eagles face a critical away trip to Gold Coast after falling back into the pack chasing finals spots.

WEST COAST                               5.0   6.2    9.3     14.6    (90)                  
GREATER WESTERN SYDNEY   2.4   4.7   8.12   14.14   (98)           

GOALS

West Coast: Kennedy 3, Vardy 2, Darling 2, Jetta 2, Petrie, Karpany, Cripps, Hutchings, Mitchell
Greater Western Sydney: Shiel 2, Cameron 2, Patton 2, Greene 2, Whitfield, Himmelberg, Kelly, Williams, Taranto, Lloyd 

BEST 
West Coast: McGovern, Sheed, Mitchell, Gaff, Yeo, Jetta
Greater Western Sydney: Kelly, Shiel, Williams, Kennedy, Ward, Greene 

INJURIES 

West Coast: Kennedy (lower leg)
Greater Western Sydney: Nil

Reports: Nil 

Umpires: Margetts, Nicholls, Fleer 

Official crowd: 37,057 at Domain Stadium