The wayward Eagles kicked just one goal in the opening half as Fremantle's intense pressure took its toll, with Pavlich the star of the show in the 17.11 (113) to 6.12 (48) rout.
Pavlich did what he liked opposed to Eric Mackenzie in the first half before comprehensively beating Mitch Brown after the long break as West Coast struggled to cope without suspended Eagles skipper Darren Glass.
But the win could come at a cost, with Pavlich, defender Luke McPharlin and midfielder Matt de Boer likely to be scrutinised by the match review panel for varying indiscretions.
Brown was left nursing a sore head when he copped a glancing blow from the back of Pavlich's swinging arm in the third quarter.
McPharlin delivered a high bump on Eagles forward Jack Darling while the young Eagle attempted to scoop up a ball, and de Boer could be in trouble for kicking out at Daniel Kerr in an attempted trip.
Pavlich, who took his season tally to 55 goals to lead Drew Petrie and Lance Franklin in the Coleman Medal race, won the Ross Glendinning medal as best afield, while Michael Barlow, David Mundy, Nat Fyfe and Hayden Ballantyne (three goals) were also crucial in the win.
The triumph kept ninth-placed Fremantle within percentage of eighth-placed North Melbourne, while fifth-placed West Coast (12-6) now face an uphill battle to land a top-four berth following three losses in their past four games.
Fremantle's triumph was in stark contrast to the round nine derby, when the Dockers were labelled "unwatchable" by Richmond legend Kevin Bartlett after they managed just 5.6 (36) in an ultra defensive display.
Fremantle were far more willing to attack this time around - especially on the counter - but it was their relentless tackling that also proved telling.
Star Eagles midfielder Kerr entered the match with a massive fitness cloud hanging over his tight hamstring, but the 29-year-old veteran showed no ill effects as he tallied 20 first-half disposals on the way to 36 for the match to go with his 11 clearances.
West Coast's score was the lowest ever in a derby, failing to surpass the 8.13 (61) they posted in round 21, 2006.