GREATER Western Sydney co-captain Phil Davis is in doubt for next week's clash with North Melbourne after being knocked out late in the third quarter of his side's loss to West Coast at Spotless Stadium.

Davis was collected by an accidental elbow from Eagle Jack Darling when he courageously ran back into a marking contest and missed the rest of the match, which the visitors won by 25 points.

The co-captain was helped from the ground by trainers but refused to go off on the stretcher, which had been called onto the ground.

GWS coach Leon Cameron said Davis was concussed by the impact.

"Hopefully it's only that, but it was a pretty big knock and we know how brave he is," he said after the match.

"Obviously he couldn't come back on, but we'll wait and see (how he pulls up).

"Phil will be an interesting one, we'll see how that pans out during the week."

It was a tough day for GWS with Matt de Boer going down with a hamstring injury in the first half. Cameron said the tough forward looks likely to miss at least one to two games.

They were already without stars Josh Kelly (groin), Brett Deledio (hamstring), Toby Greene (foot), Tom Scully (ankle) and Zac Williams (Achilles) for the West Coast game.

Greene, Scully and Williams are long-term outs, and while Deledio could be back to face the Kangaroos, All Australian midfielder Josh Kelly is less likely to be fit after missing five matches.

"When you're down on form there's always that decision where you can reach out for your players that are coming back from injuries and whether you go down that track," Cameron said.

"But we've got to be really careful of that, and he's (Kelly) had a really good week and a half but if he's not right, he's not right.

"We'll see how he goes this week."