AND THEN there were four.

Three of this weekend's preliminary finalists – Adelaide, Brisbane and Collingwood – have occupied top spot at one stage of the home and away season, while plucky Melbourne's giant-killing month has played out from the middle rungs of the ladder.

All are "foundation" teams of the NAB AFLW competition, and the Lions and Dees still have their inaugural coaches in Craig Starcevich and Mick Stinear. Last week, the latter became the first to record 25 wins.

Adelaide and Brisbane have been here before: the Lions lost the 2017 and 2018 Grand Finals, while the Crows were premiers in 2017 and 2019.

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Melbourne has always been thereabouts, while the Pies have made a slow but steady march up the ladder over the past five years.

Looking at the numbers, the quartet have different styles of play.

The Pies are clearly a handball-happy team, averaging comfortably the most handballs and a kick to handball ratio of 1.32:1.

It should make for an interesting battle against the Lions, who average 21.6 fewer handballs with a kick to handball ratio of 1.77:1.

Curiously, Collingwood also average the most marks of the group despite recording the fewest kicks – the team prefers a short kick direct to a teammate rather than a long kick to open grass.

The other preliminary final will see Melbourne and Adelaide face off at Adelaide Oval.

It'll be a clash between two talented, high-pressure  teams with no discernible difference in their basic stats.

Interestingly, Melbourne is marginally a better clearance side than Adelaide despite the presence of multiple All-Australian midfielders Ebony Marinoff and Anne Hatchard in the Crows' engine room.

The Dees' goalkicking yips – which can even rear for just a quarter or two during a match, as seven consecutive behinds against Fremantle proved – have been well-documented, but Adelaide have regularly had inaccuracy issues of its own.

The difference between the two is the sheer weight of shots; Adelaide leads the competition in both average inside 50s and, most importantly, goals.

With the likes of Erin Phillips, Chelsea Randall, Ashleigh Woodland, Chloe Scheer and Danielle Ponter up forward, Melbourne will have to be on its guard against the minor premiers.