It was back-to-back victories for the developing Hawks as they won 15.12 (102) to 12.5 (77) in cold and showery conditions.
Experienced mid-sized forward Luke Breust showed the way with a career-equalling six goals, the last one late in the last quarter to ice the game after the brave but undermanned Eagles kept pressing throughout the contest.
Breust's goals haul was timely as young key forward Mitch Lewis was kept scoreless by Eagles defender Tom Barrass, who had a career-high 30 possessions including 18 marks.
The Hawks maintained scoreboard control following a 6.0 to 3.1 second quarter, but the home team had to respond several times as West Coast found answering goals to stay in touch.
The on-ball combination of Brownlow Medallist Tom Mitchell, with 32 possessions, and rookie Jai Newcombe (28 touches) gave the Hawks ample opportunities to surge forward.
And their trademark rebounds from defence netted at least half a dozen goals on the way to an impressive win.
Breust, a triple premiership player, said it was exciting to still be a part of the next resurgence of this Hawthorn team.
"You've got to go through some hard yards and at the moment we're just building," he said.
"The effort and the brand of footy we're trying to play is improving each week.
"You get games like today where you really take a step forward. There's some players in this group that I can't wait to see what they do in the next few years."
Hawthorn were given an early reminder of the danger posed by West Coast's key forward targets as Jack Darling marked and goaled inside the first minute.
Josh Kennedy added another with a quick kick off the ground in the goal square, but both Eagles big men could manage only two each against Hawks new boy James Blanck and the reliable James Sicily.
A heavy downpour just before the game presented players with a wet, greasy ball, and while the opening quarter was an even slog, handling became easier when the sun reappeared.
It was the Hawks who grabbed the initiative after a stern pep talk from skipper Ben McEvoy at the quarter-time break.
Hawthorn's bold rebounds down the centre corridor put the Eagles' defence under pressure, and Breust, Will Day, Dylan Moore and Connor Macdonald kicked unanswered goals to provide a scoreboard buffer.
But West Coast proved more than a match in the contested-ball battles, and late goals from Jake Waterman and Liam Ryan kept the visitors in touch to set up an engrossing second half before Hawthorn finally asserted control.
Midfielder Jai Culley, picked up in the mid-season rookie draft, debuted for West Coast.
That underlined the Eagles' woes in a season interrupted by illness and injury as Culley was the 47th player used this year and ensured an appearance from every player available on the WA club's senior list.
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