For years, American players have been propping up our national W-League, with Australia doing the same for the US's National Women's Soccer League (NWSL).

Key points: Three players from US side Carolina Courage, which won the national title last month, have joined Western Sydney Wanderers

Three players from US side Carolina Courage, which won the national title last month, have joined Western Sydney Wanderers Football Federation Australia is in talks with the US league over formalising transfers of players

Football Federation Australia is in talks with the US league over formalising transfers of players Last season, 35 US players joined Australian sides in their off-season

It's an enormous outlay for the players, with many taking on back-to-back seasons across two hemispheres, most famously in the shape of Sam Kerr, who cut multiple years across Perth Glory and US teams in Chicago and New Jersey.

Back in Australia, in a huge coup, the Western Sydney Wanderers have called in three of the US's championship-winning players in a bid to help the side go from last season's wooden-spooners to the next ladder leaders.

The three recruits — Denise O'Sullivan, Lynn Williams and Kristen Hamilton — all hail from Carolina Courage, which claimed its second-straight NWSL title on October 27.

Lynn Williams celebrating with teammate Tobin Heath. ( Supplied: NWSL )

Ten days after the win, they were strapping on their boots for the Western Sydney Wanderers.

"Everyone has been great so far, but it's a transition having played with the same team for the past five years in North Carolina," said striker Hamilton.

Hamilton is the W-League's leading goalscorer so far in four rounds since the season started on November 14.

She pulled off the Wanderer's first-ever hat-trick, against Brisbane Roar, at the end of last month.

Denise O'Sullivan said they have brought with them the momentum from the NWSL title win.

"The second championship was a feeling I can't describe. It's just so professional, we worked very hard and it's amazing having these two girls here with me now — we can bring our quality here," O'Sullivan said.

Denise O'Sullivan is one of the new US players. ( Facebook: Western Sydney Wanderers )

Last season, 35 NWSL players came to play Australia's top-flight competition in their off-season over October to April.

"It works perfectly, we can play in both seasons and to play year-round is important for women's football," Hamilton said.

"You see Australia's national team doing really well and obviously the US, so it's a great partnership."

Lynn Williams also brings with her experience of playing for a side with underdog status.

"Knowing the story of the Wanderers, they've had troubles in the past — it reminded me of my start in western New York," she said.

"I feel like if we can get there, it could be something really special."

Lynn Williams (second from right) warms up. ( Facebook: Western Sydney Wanderers )

Williams has also made her presence felt, with the most shot attempts in the league so far — 16 in three games.

"The NWSL is more of an athletic league, there's a lot more running that goes on and a lot more fitness there," she said.

"I think there needs to be more support to give players more time off between leagues."

Denise O'Sullivan, who's also an Irish international, loves staying match fit, but after three seasons with the NWSL agrees player fatigue could be an issue.

"Playing in America is a very high-level league. It's pretty intense so you're very tired by the end of that," she said.

Sam Kerr played eight back-to-back seasons between the US and Australia but now has been lured to Chelsea FC where she starts a two-and-a-half-year contract worth nearly $2 million in January.

"The European leagues are really getting strong, the English league is coming on leaps and bounds so players may go there like Sam Kerr has, but with these leagues growing [in the US and Australia], hopefully we get players to stick around," O'Sullivan said.

Kerr signed with Chelsea in a deal reported to be about $600,000 a year. ( Supplied )

That growth has been astounding — attendance in England's Women's Super League was four times higher last season than the previous.

Manchester City's derby victory over Manchester United drew a record crowd of 31,213 in September and Tottenham Hotspur is averaging crowds of more than 15,000 a game.

England's national team also drew a record crowd of 77,768 against Germany last month in London's Wembley Stadium.

But Williams warned that European leagues pay more and are subsequently more sustainable for players in giving them a living wage.

"If people want to keep players here in Australia and the US, you're going to have to start paying your players [more]," Williams said.

US-Australia deal on the cards

Football Federation Australia has told the ABC discussions are underway between the W-League and the NWSL about setting up a formal arrangement between the US and Australia.

"The discussions are preliminary and mostly focused on the alignment of the season windows to allow players to play in both leagues," an FFA spokesperson said.

In the W-League's 11-year history, the Wanderers have never been season premiers or won the championship, nor has a wooden-spooner ever made the following season's finals.

"People were always doubting Carolina Courage and saying they can't do it again, they aren't as good as they were last year, and we proved that [we were]," Williams said.

"If the Wanderers can come from last year and step up our game, it's only going to continue to push this league more and more, and I'm so happy to be a part of it."