The Dockers won their third consecutive derby under Ross Lyon 19.7 (121) to 14.9 (83).
They were made to earn it.
West Coast was missing eight senior players but through fanatical tackling pressure and an outstanding five-goal display from Jack Darling, led by two points at three-quarter time.
But the Dockers kicked eight goals to three in the final term to make a significant statement that they are unequivocally the No.1 team in town in 2013.
Fremantle's stars took control in the last quarter. Michael Barlow claimed his second consecutive Ross Glendinning Medal after collecting 26 touches and two goals, Nathan Fyfe had 30 disposals, David Mundy 28, and Stephen Hill 27 and two goals in a brilliant 100th game.
Freo's bigger bodies were telling in a frenetic opening term.
West Coast elected not to tag any Fremantle midfielders and the Dockers feasted, collecting 22 more possessions for the quarter to lead by 11 points at the first change.
They extended the lead to 18 points by the seven-minute mark of the second term after Michael Walters and Matthew Pavlich converted set shots.
The momentum swung on a soft 50m penalty that led to Darling's third goal of the first half. Will Schofield then braved life and limb to take a mark going back with the flight that resulted in a goal to Jamie Cripps.
Schofield then drifted forward and jagged a freakish goal from the boundary and the Eagles deserved their one-point lead at half-time.
West Coast's tackling pressure was extraordinary. The Eagles laid 60 tackles to 37 in the first half.
The third term was pulsating, compelling viewing. The two sides traded 10 goals between them as the game went from a war of attrition to a shootout.
Tempers also flared following two heavy hits. Clancee Pearce was subbed out with concussion after Andrew Embley collected him while his head was over the football.
While Embley was not reported, Fremantle captain Matthew Pavlich was for a similar bump on Mitch Brown.
WEST COAST 2.3 6.5 11.8 14.9 (93)
FREMANTLE 4.2 6.4 11.6 19.7 (121)
GOALS
West Coast: Darling 5, LeCras 2, Schofield 2, Kennedy 2, Cripps 2, Embley
Fremantle: Walters 3, Mayne 3, Pavlich 3, Barlow 2, Hill 2, Mzungu, Crowley, D Pearce, Fyfe, Sutcliffe, Sheridan
BEST
West Coast: Darling, Glass, Embley, Mackenzie, Priddis, Hutchings
Fremantle: Mayne, Fyfe, Barlow, Hill, Mundy Walters, Spurr
INJURIES
West Coast:
Fremantle: Suban (calf, replaced in selected side by Sutcliffe), C Pearce (concussion)
SUBSTITUTES
West Coast: Cale Morton replaced Matthew Rosa during the third quarter
Fremantle: Cameron Sutcliffe replaced Clancee Pearce during the third quarter
Reports: Matthew Pavlich reported for rough conduct against Mitchell Brown during the third quarter
Umpires: Farmer, Jeffery, McInerney
Official crowd: 39,839 at the Patersons Stadium
