Newcastle have all but ended Sydney FC's A-League Women title defence with a 1-0 win over the reigning champions.

And Adelaide United have jumped to second on the table with a 1-0 win over Central Coast.

In Newcastle, dual code star Sheridan Gallagher tapped home her fourth goal of the season in the 42nd minute to give the Jets' season a pulse.

Newcastle (17 points) are 10th and seven points outside the top six with five games to go.

But for last-placed Sydney, now 11 points and a hefty whack of goal difference outside the finals places, reaching the play-offs would take a miracle.

Ante Juric's side, who were premiers for the past three seasons and champions the past two, would likely need to win all their remaining games and hope for slip-ups from the likes of Central Coast, Brisbane or Canberra.

The Jets were good value for their three points, recording 15 shots (eight on target) to Sydney's nine (two).

But they found the crucial moment when Emma Dundas slipped a through-ball out to Lorena Baumann on the left.

Baumann's cross to the back post was well met by Lauren Allan, who forced a strong save from Bethany Mason-Jones, but Gallagher was on hand to tap home.

Gallagher made way at half-time, while the Jets will have concerns over a leg injury to Josie Allan, who was forced off just after the hour.

Sydney's day grew worse when Mason-Jones had to come off in the 72nd minute.

The Reds hosted Central Coast at Coopers Stadium and were out-shot 17-7 on their home deck - but found the clinical moment in front of goal in the 50th minute.

Erin Healy pounced on the ball at the edge of the area, danced onto her right and coolly finished.

It was American attacker Healy's sixth goal of the season.

Central Coast's day became harder when Shadeene Evans received her second yellow card in the 61st minute.

Adelaide (36 points) are now four points behind leaders Melbourne City and one ahead of Melbourne Victory, while the sixth-placed Mariners (24 points) are precariously placed ahead of the run to finals.