The Dockers at one stage had 23 handballs to the Lions' four as the battling AFL side looked to explode out of their rut.
But a lack of polish hurt them in a 17.13 (115) to 10.7 (67) loss that sunk the side, tipped to fight for a premiership this year, to 2-5.
Brisbane slowly constricted the visitors at the stoppages, Lachie Neale collecting 15 clearances on his own in a 46-29 count to the Lions that led to regular scoring opportunities.
Two-time Brownlow Medallist Fyfe has been out with a foot injury since the first round but Longmuir said he could play against Hawthorn next week in a timely boost with their season in the balance.
"I think he'll play some footy next week if the weekend goes well," the coach said.
"It's been a week-to-week proposition so until he gets the all clear we haven't really broached where he's going to play or his transition back.
Longmuir said he was happy to see the "dare" in the Dockers play even if they hadn't quite nailed it.
"It's about trying to fight the risk of players internalising and being caught up in doubt," he said of how they're coping with another heavy loss.
"We need to keep giving them the confidence to be able to execute what we're trying to execute.
"I'll keep reinforcing that ... I'll keep changing things up. It was probably the most mids we played all year.
"Spin the numbers through there and give some guys a chance."
Brisbane coach Chris Fagan admitted Fremantle had tested them early.
"They were ballistic in the first quarter, trying to play so fast," he said.
"They came to play fast and we expected that and I thought our response was pretty good."
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