All-star Melbourne City will head into next month's finals series as near-unbackable favourites to win a fourth W-League championship in five seasons after locking up top spot on the ladder with room to spare.

City hit four unanswered goals to sweep aside third-placed Western Sydney Wanderers with ease at Marconi Stadium and claim the premiership with a round to spare.

Ellie Carpenter bagged a double, sandwiched between goals from international pair Claire Emslie and Ally Watt.

The win was City's tenth in succession and the club's seventh clean sheet in a row.

Another perfect defensive performance in next week's final-round outing against Brisbane Roar will ensure City eclipse their own competition record for fewest goals conceded in a season set in 2016.

That campaign also included 12 straight wins, and with potentially three matches left in the season, that mark is another W-League record City's sights.

Captain Steph Catley believes the current City side are a more complete side now compared to four years ago.

"I actually think the football and the consistency in which we are playing is at a higher level," said Catley.

"It has felt amazing this year."

City won a string of games by a single goal earlier in the season but have now netted 14 times in their past four outings.

City defender Emma Checker believes the side is supremely confident in their own ability following some scratchy performances earlier in the season.

"We are really focused on how we are playing, and knowing that if we get our part of things right we can come out on top in any game," she said.

"Now it is just a case of keeping our standards high because that is what has got us where we are now, and that is what will keep us going (to the championship).

The 4-0 scoreline meant the Wanderers' late season freefall continues unabated and their charge for a maiden semi-finals berth will not be determined until next week's final round.

Even the status of perennial finalists Sydney FC has diminished in recent weeks with star players Caitlin Foord and Chloe Logarzo making the move to the English Super League.