A Jamie Cripps final minute goal has secured the Eagles a big on the road victory against the Hawks.
The Eagles led by 20-points at half time before the Hawks charged back into the game to lead by less than a goal at the final change.
West Coast have now won five consecutive matches at the MCG following the 11.11.77 to 9.17.71 triumph.
Nic Naitanui on his return from his second knee reconstruction whacked 40-hit outs, had six possessions and failed to take a mark.
Jack Darling booted five goals, Jamie Cripps three and Luke Ryan two.
The Eagles are now in equal second position on the ladder and face the Dockers in the derby on Saturday night.