As Matildas flock to Europe, the PFA says the W-League must decide whether it wants to be a development competition or compete with the world's top leagues.
As Australia prepares to co-host the 2023 FIFA Women's World Cup, the W-League is at risk of falling behind the world's top women's football leagues.
In their 2019-20 W-League report, the PFA said the domestic league could be relegated to the "third or fourth" option for Australian female footballers, as Europe becomes an increasingly popular destination.
Australians have turned away from America's NSWL in favour of Europe, with the report noting 93 per cent of the country's women players abroad are now based in Europe - compared to 39 per cent this time last year.
But while those who plied their trade in the NWSL would previously complete two seasons per year - moving between America and the W-League - this simply isn't an option in most European leagues.
It means the W-League also loses the majority of the Matildas who featured over the past two seasons.
Earlier this month, FFA chief executive James Johnson said there was an opportunity to make the W-League one of the world's top five leagues.
PFA co-chair Kate Gill said the W-League needed to decide whether it wanted to be a development competition or compete with the world's best and invest accordingly.
"With the emergence and attraction of European 'powerhouse' clubs and leagues, the W-League must consider its place within football's ecosystem to ensure the career pathway for Australian footballers is dignified and legitimate," Gill said.
"For example, is the W-League a world-leading development pathway designed to catapult our most talented players into the international market?
"Or is there an opportunity for the W-League and NWSL to work collaboratively to provide a calendar year of football and a partnership that serves both our international and domestic game?
"We must explore these options and ensure whatever approach we adopt, female football in Australia does not regress and the momentum of significant gains built over the past five years continues."
England's Super League is the most popular for Australians, with surveyed W-League players ranking the competition their preferred league to play in, followed by the NWSL, other European competitions then the W-League.
Captain Sam Kerr (Chelsea), Caitlin Foord (Arsenal), Hayley Raso and Chloe Logarzo (Bristol City) were the first Matildas regulars to sign at English clubs.
More recently, Matildas vice-captain Steph Catley and first-choice goalkeeper Lydia Williams joined Foord at Arsenal while young gun Ellie Carpenter signed with French powerhouse Olympique Lyonnais.
Defenders Alanna Kennedy, Laura Brock and Jenna McCormick and midfielders Emily van Egmond and Aivi Luik are also expected to move to Europe.
Australians in top European leagues:
England: Sam Kerr (Chelsea), Steph Catley (Arsenal), Caitlin Foord (Arsenal), Lydia Williams (Arsenal), Hayley Raso (Everton), Chloe Logarzo (Bristol City), Ella Mastrantonio (Bristol City), Mackenzie Arnold (West Ham), Jacynta Galabadaarachchi (West Ham).
France: Ellie Carpenter (Olympique Lyonnais), Mary Fowler (Montpellier), Emma Checker (FC Fleury 91).
Netherlands: Kyah Simon, Amy Harrison (both PSV Eindhoven).
Norway: Karly Roestbakken (LSK Kvinner FK), Clare Polkinghorne, Katrina Gorry (both Avaldsnes IL), Tameka Yallop (Klepp IL), Teagan Micah (Arna Bjornar), Nikola Orgill (Kolbotn).
Spain: Alex Chidiac (Atletico Madrid).
Sweden: Elise Kellond-Knight* (Kristianstads DFF).
* Out for the season through injury