West Coast has escaped from a nail-biting arm wrestle against the GIANTS with arguably its most important victory for 2018, a gritty 11-point triumph at Optus Stadium on Sunday.

After three straight losses since the bye, the once high-flying Eagles were in freefall and looked in serious jeopardy of wasting their 10-1 start and coughing up a crucial top-four spot.

But in an epic finish to round 16, Adam Simpson's men held off the surging GIANTS, buying themselves some valuable breathing space in the run to finals with a 13.8 (86) to 10.15 (75) triumph.

The victory sets up a massive encounter at the MCG next round, when the third-placed Eagles will face off with second-placed Collingwood, while 10th-placed GIANTS' season could be on the line in another blockbuster against Richmond. 

The GIANTS have dropped from sixth spot on the ladder following the loss in Perth and are half a game outside the top eight.

Talismanic ruckman Nic Naitanui was relatively quiet before half-time after battling soreness all week.

However, after copping criticism for not standing up when it mattered against Adelaide last round, the big man took two Mark of the Year contenders in an almost identical spot in the second half which noticeably lifted his teammates as they held on for an epic win. 

Sunday's clash wasn't without plenty of nervous and controversial moments in the dying stages.

From 23 points up into time-on of the third quarter, the Eagles watched as the rampaging GIANTS ate up the deficit with a stunning four-goal burst either side of the final break.

Both sides' forward lines were decimated, and it was Adam Tomlinson (three goals) and Stephen Coniglio who inspired the visitors.

When star half-back Lachie Whitfield put the GIANTS in front with a long-range major at the 11-minute mark of the final term, Leon Cameron's men had all the momentum.

Prolific Eagle Andrew Gaff's (41 disposals, two goals) brilliant snap wrestled back the lead, but only momentarily before Harry Himmelberg was awarded a holding the ball free kick against Tom Cole from 20m out directly in front of goal, which incensed the 52,105-strong crowd.

But, fittingly in a week when Hawthorn superstar Cyril Rioli announced his shock retirement, it was some magic from cousin Willie which secured a famous West Coast win.

Rioli's mark and long-range set shot handed Simpson's side a seven-point lead, and when Jeremy McGovern (two goals) took advantage from a free kick moments later the Eagles had done enough.

At 11-4, the Eagles are a win clear of fifth-placed Sydney and will cross their fingers at least one of star forwards Josh Kennedy or Jack Darling will be back from injury next round.

The GIANTS were missing twin towers Jeremy Cameron (suspended) and Jon Patton (ACL), plus gun small Toby Greene.

In their absence, Tomlinson and Himmelberg combined for five majors, while Coniglio (30 disposals, one goal) did everything in his power to lift the visitors.

Gaff was simply superb for the Eagles, while Elliot Yeo (32, four clearances) relished a move back to midfield and skipper Shannon Hurn (24 disposals) saved the Eagles on numerous occasions.

Mark Hutchings performed an excellent shutdown job on Josh Kelly (26 disposals) and hit the scoreboard with two majors by half-time as the Eagles edged out to a 13-point buffer at the long break. 

MEDICAL ROOM
West Coast: Naitanui got up sore after landing heavily from his first Mark of the Year contender but played on and the Eagles seemed to get through unscathed. 

GIANTS: The Giants appeared to come out of the game without any injury concerns.

NEXT UP
The Eagles face a daunting challenge travelling to the MCG to take on rampant Collingwood, while it is almost do-or-die time for the GIANTS against runaway League leader Richmond back at Spotless Stadium.

WEST COAST 1.2   6.3   10.3  13.8 (86) 
GIANTS 2.2   3.8  7.12   10.15 (75)  

GOALS
West Coast: Rioli 2, Hutchings 2, Cripps 2, Gaff 2, McGovern 2, Lycett, Ainsworth, Redden  
GIANTS: Tomlinson 3, Himmelberg 2, Whitfield, Ward, Perryman, Coniglio, de Boer,  

BEST 
West Coast: Gaff, Yeo, Hurn, Redden, Hutchings, Shuey, Naitanui
GIANTS: Coniglio, Whitfield, Tomlinson, Taranto, Himmelberg, Ward 

INJURIES 
West Coast: Nil     
GIANTSNil

Reports: Nil 

Umpires: Meredith, Findlay, Gianfagna 

Official crowd: 52,105 at Optus Stadium