A sell-out crowd of almost 60,000 fans will greet the Dockers for Saturday night's elimination final against Gold Coast at Optus Stadium, but it could be a wet one with between 2-15mm of rain forecast for the day.
The Dockers struggled to handle wet and slippery conditions in recent years, but they have turned it into a strength in 2025.
Their most notable wet-weather win this season was on the Gold Coast, when their ability to thrive at ground level helped deliver an upset 11-point win.
"If it rains, it rains. I look forward to the rain. I think we're 5-0 in wet games this year," Longmuir said on Thursday.
"It suits the way we play. When the ball's on the ground more often than it's in the air, we've flourished in those conditions.
"I understand that they've got some bulls in there and it probably leans into their strengths as well, but I back our guys in."
The "bulls" Longmuir refers to is Gold Coast's star-studded midfield.
Jarrod Witts is now one of the best tap ruckmen in the league, while Matt Rowell, Noah Anderson and Touk Miller are all A-grade midfielders.
Fremantle boast Sean Darcy and Luke Jackson in the ruck, while their superstar midfield features Caleb Serong, Andrew Brayshaw, Hayden Young and Shai Bolton.
Longmuir feels he has the "best ruck combination in the comp", and he's backing his team to get it done at ground level as well.
"Our contest and contest method is in really good order," Longmuir said.
"When the game leans to more of a ground ball game, our game comes to life, and that tends to be the case in finals.
"Our record against the better sides has been been good this year, so our players should go into this with a lot of belief."
Saturday's match will mark Nat Fyfe's last appearance in Perth, while Gold Coast also have plenty of motivation in the form of retiring former skipper David Swallow.
Fyfe hasn't played a final since 2015, and West Coast great Glen Jakovich made the bold statement this week that the two-time Brownlow medallist should be dropped.
Longmuir quickly dismissed any possibility of that.
"I haven't got my advice from outside the four walls at anytime this season," Longmuir said.
"I understand everyone's got an opinion and everyone's got the right for an opinion, but yeah, that won't be happening.
"Hopefully we can keep his career going and make it more than just one final."
Dockers forward Sam Switkowski (knee) has been ruled out of the match, while Corey Wagner (pec surgery) will miss the rest of the season.
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