West Coast unveiled their 2018 flag before flexing their premiership muscle with a 52-point win over GWS at Optus Stadium on Saturday night.
The Eagles copped a big wake-up call in last week's 44-point loss to Brisbane, and they were desperate to avoid a 0-2 start to the season.
Alarm bells were ringing when GWS edged to a two-point lead midway through the second term.
But West Coast booted the next five goals in a 12-minute blitz to help set up the 16.8 (104) to 7.10 (52) win in front of 54,985 adoring fans.
GWS won the inside 50m count 62-47, but their sloppy entries cost them dearly.
Giants midfielder Lachie Whitfield was stunning with 33 disposals and five clearances in a hard-running display, but his teammates lacked the same polish.
West Coast's Norm Smith medallist Luke Shuey tallied 28 disposals and two goals, while Jeremy McGovern was a rock in defence with 11 marks.
Jack Darling booted four goals and Oscar Allen three, but Josh Kennedy (1.3) was rusty in his return from injury..
Ruck recruit Tom Hickey made up for last week's quiet display with 20 hit-outs, 18 possessions, and eight marks in his first home match for the Eagles.
West Coast unfurled their premiership flag in entertaining style before the match, with the Eagles mascot backflipping off the stadium's roof before ziplining his way to the middle of the oval with the flag attached.
Eagles players had plenty of motivation given Kennedy, Chris Masten, and Shannon Hurn were celebrating significant milestones.
But it was GWS who controlled the early stages.
Whitfield was unstoppable in the first term with 12 disposals, and he continued the onslaught in the second term as the Giants' run-and-stun style looked set to tear the game wide open.
But their inability to make the most of their forward thrusts came back to haunt them as West Coast finished the second quarter with a goal blitz take a 28-point lead into half-time.
GWS entered the long break with the sombre knowledge they had scored just three goals from their 36 inside 50s.
In contrast, West Coast booted eight goals from their 23 entries - an efficiency that proved to be the difference.
West Coast's marking power in attack was also causing GWS problems.
The Giants' hopes of a comeback in the third quarter were brought undone by two separate 50m penalties that cost them goals.
And when Dom Sheed relived his grand final glory with a goal from the pocket, West Coast headed to the final break with a 31-point lead and the game effectively in the bag.