MINOR premier Brisbane unknowingly did Melbourne a favour with its round four win over the Demons.

It made Melbourne stop and ponder how the Lions could so easily cut through them on the field.

Six weeks later, the Demons are the best defensive team in the league and will carry an impressive statistic into Friday night's qualifying final against Adelaide at Ikon Park.

AFLW FINALS Get your Demons-Crows tickets now

They are only the second team in AFLW history to keep opponents scoreless in the opening quarter for four straight weeks.

Lauren Pearce and Sarah Lakay compete for the ball in the round 10, S7 match between Melbourne and West Coast at Casey Fields. Picture: AFL Photos

As star defender Libby Birch explains, that has been no accident.

"We got shown up by Brisbane in the middle of the year and that was a really important loss," she told AAP.

"It showed us that team defence can't just be the backline. It has to be a team effort.

"That's something we've specifically worked on over the last five or so weeks. That's been a huge focus for us.

"I guess it's something we've nailed from an outcome point of view, but there's still lots of room for improvement in games and making sure we continue to nail that under finals pressure."

Libby Birch, Daisy Pearce and Blaithin Mackin sing the Melbourne team song after defeating Essendon in round nine, S7 at Casey Fields. Picture: AFL Photos

Melbourne has not lost since it went down to Brisbane, while the Demons also achieved their key goal of having the least points kicked against them.

The Demons missed out on the minor premiership by one point, but they still have the double chance and a home qualifying final and their form is a welcome confidence boost coming into this finals series.

Melbourne lost last season's grand final to Adelaide and are perennial premiership fancies who have never claimed the AFLW flag. But Melbourne started this season with a win over the Crows, putting that bad memory to bed, and they built from there.

04:50

"Our round-one match against Adelaide was really important for us. It was more, for us internally, to know we can develop our game style to beat a quality side like Adelaide - and we'd never done that before," Birch said.

"Finals is obviously a different ball game and Adelaide are a very quality side. It's going to be on from the first bounce.

"There's no doubt we've fallen short many times and for us, this year has been about building on what we didn't have in season six."

Libby Birch in action at a training session on April 7, 2022. Picture: AFL Photos

Birch, who wrote a comment piece about sports psychology last month, continually goes back to process goals.

Given Melbourne's rich talent and form - and its historic inability to win a premiership - clearly what happens between the ears will be crucial for them over the next four weeks.

"We're not even thinking about the grand final at the moment because we're not there. That is way down the track for us," she said.

"The history of these two teams (Melbourne and Adelaide) is massive and it's exciting for fans. It's going to be a hot contest, it always is."