WEST Coast coach Adam Simpson offered no excuses for his team's deplorable opening quarter in Thursday night's defeat against Essendon, which has left the Eagles' top-four ambitions on shaky ground.

Simpson's outfit was the best first-quarter team in the competition heading into the Optus Stadium clash, winning 10 this year, but inexplicably went missing from the opening bounce.

The Bombers ran riot early, taking the game on from half-back and outhunting the home side at the contest (37-30) and clearances (12-8).

BOMBER BLITZ DOWNS EAGLES Full match coverage and stats

Essendon was on fire, shooting out to a 37-point lead at the first change after booting six unanswered goals, while the Eagles were shambolic.

Simpson refused to blame his side's horror start on a six-day break, or due to the absences of star forwards Josh Kennedy (knee) and Jack Darling (ankle), instead declaring the Bombers were just too tough.

West Coast clawed back into the match and had 59 inside 50s to 45 by the final siren, but only 6.16 to show for it in a 28-point loss.

"We can say nothing went right for us in that first half or that first quarter – and that's not far off – but that would discredit what Essendon did and their intent early," Simpson said post-match.

"I'm not going to offer any excuses. We were poor in the first quarter, they were really good and we got what we deserved."

DONS DO IT ON THE ROAD Five talking points

The Eagles dominated after the first break and had 21 scoring shots to 12, but their radar was miles off without reliable goalkicking sources Kennedy and Darling for the first time since 2011.

"If we played every quarter like the last three, then we could sit here and go 'we've got some work to do with missing our key position players'," Simpson said.

"But the first quarter was separate to that, so I think we've got to park the conversion and park the forward 50 connectivity (talk) and we've got to concentrate on the start and what happened there.

"We got jumped by a team that was tougher than us, so that's what we've got to fix."

West Coast blew a golden opportunity to move back a game clear on top of the ladder on Thursday night and is now in third spot, with a chasing pack not far behind in the hunt for top-four spots.

The Eagles (10-3) have a testing run ahead against Adelaide (Adelaide Oval), Greater Western Sydney (Optus) and Collingwood (MCG), and Simpson was aware he needed to ensure his players weren't too despondent after the shock Bombers loss. 

WATCH Adam Simpson's full post-match media conference

"A bit of white noise is going to come, I get, we've been there and done that a little bit," he said.

"We've just got to be mature about it and our leaders need to stand up.

"I've got the players' back, our club is a sanctuary when they come into it and that won't change whether we've won by 10 or lost by 10, I'll still back them in. 

"We need to play with a bit more spirit, that's a been a hallmark of our performances, and the kids have energised us this year, but that doesn't last all year.

"We need to find ways to keep the energy going."

Simpson expected Kennedy would try to prove his fitness for the Adelaide clash but was no certainty.

"Hairline fractures are very small fractures," he said.

"It's not perfect news, but it's a pretty good result considering what we thought might have happened."