WEST Coast officially has a weakness, and Port Adelaide has taken full advantage to post a 42-point win at Optus Stadium on Good Friday.

In a game that featured periods of driving rain, Port booted nine goals to two in the opening half to set up the 13.17 (95) to 8.5 (53) triumph.

The Eagles have proven to be the kings of dry-weather football, but the shortcomings of the defending premiers have been clear to see when things get slippery.

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In round one against Brisbane, West Coast copped a 44-point hammering in greasy conditions at the Gabba.

And against the Power in front of 49,290 fans, the Eagles’ big guns could barely fire a shot in the wet and windy conditions.

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Key forwards Josh Kennedy, Jack Darling and Oscar Allen managed just one goal between them, with West Coast only avoiding an annihilation courtesy of a five-goal haul to speedster Jack Petruccelle.

In contrast, the slick and fast Power had 10 different goalkickers in a dazzling team display.

Port led by 49 points at half-time, an astonishing figure given the downpour in the first half.

Some Eagles fans left the stadium at that point, such was their dismay at how poorly their team was playing.

The six-goals-to-one second term tore the game wide open, with West Coast's defence unable to cope with the constant Power raids in the driving rain.

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With tall timber Kennedy, Darling, Allen, Tom Hickey and Nathan Vardy proving to be ineffective in the wet, Port Adelaide cashed in.

Former Eagle Brad Ebert and Xavier Duursma booted two goals each in the first half, while Willem Drew snapped a ripper from the pocket as lightning flashed in the background.

Darling had a moment of madness just before half-time when he gave away an off-the-ball free kick and then a 50m penalty for slinging Riley Bonner to the turf.

West Coast showed a bit more fight in the second half when the rain stopped, but the game was already over.

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Power co-captain Ollie Wines was superb with 35 disposals, seven clearances and a goal, while Tom Rockliff, Sam Gray, and Sam Powell-Pepper were also influential.

Eagles skipper Shannon Hurn and Brad Sheppard fought valiantly in defence, while Petruccelle's pace helped him to boot his career-high five goals.

But West Coast boasted few other winners in a game where Port Adelaide won the inside-50m count 69-38.

The result leaves both the Power and Eagles with 3-2 records.

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MEDICAL ROOM
West Coast: The Eagles appeared to get through unscathed on an otherwise dirty night.

Port Adelaide: Young gun Connor Rozee came off during the opening term after Elliot Yeo stood on his right leg. Rozee's ankle was looked at and knee strapped before returning late in the quarter. Powell-Pepper had ice applied to his left calf after coming off late in the final quarter.

NEXT UP
The Eagles face arguably their toughest road test for the season next Sunday down at the Cattery against Geelong, where they have lost five-straight, and the Power will start strong favourites on Friday night in a home clash with out-of-sorts North Melbourne. 

WEST COAST       1.1   2.2    5.3      8.5 (53)
PORT ADELAIDE  3.5   9.9  12.12   13.17 (95) 

GOALS
West Coast: Petruccelle 5, Ryan, Kennedy, Gaff
Port Adelaide: Ebert 2, Duursma 2, S.Gray 2, Powell-Pepper, Drew, Marshall, Ryder, Wines, Rozee, Houston 

BEST 
West Coast: Petruccelle, Sheppard, Hurn, Jetta, Ryan
Port Adelaide: Boak, Wines, S.Gray, Powell-Pepper, Lycett, Rockliff 

INJURIES 
West Coast: Nil
Port Adelaide: Rozee (ankle), Powell-Pepper (calf) 

Reports: Nil

Umpires: Fisher, Stephens, Ryan

Crowd: 49,290 at Optus Stadium