United's play-off path took a turn for the worst in a 5-1 rout at the hands of the Newcastle Jets - who booked their second trip to the W-League finals - in front of 1117 at McKellar Park on Sunday.

Fifth-placed Canberra remain locked in a three-horse race for the last two spots in the semi-finals alongside Newcastle and Melbourne City but they're looking the least likely to launch a championship bid.

A loss to Newcastle makes United's push for a finals berth extremely difficult, sitting in fifth and one point behind Melbourne City. United would need City to lose to the Jets on Saturday and then beat second-placed Brisbane on Sunday to force their way into the top four.

United have only ever missed the finals once - when they finished fifth and two points outside the top four in 2012-13 - and head coach Heather Garriock is shattered the number could grow in her first season at the helm.

"If we got the three points we're celebrating, through to finals football," Garriock said.

"It's disappointing but I can't fault the effort of the girls. Most importantly I think we were in the game initially and then in the second half just not good enough.

"Coming into the season as a coach I really felt by recruiting a goalkeeper and two defensive players, I really felt that it was important to have a really strong defence, especially the spine as well.

"It just hasn't been like that, I'm not sure why."

United fell behind in the 12th minute when Emily Van Egmond found the back of the net, and Garriock soon leapt out of her chair in dismay when Newcastle went 2-0 up through hat-trick hero Katie Stengel.

Referee Rebecca Durcau let play continue despite what some deemed a clear infringement on a Canberra player seemingly being pulled to the ground, paving the way for the Jets to score.

United were their own worst enemy as they struggled to clear their own line - that is until Heyman found Ellie Carpenter streaming down the right edge.

Carpenter capped off a superb run and finish with a dazzling strike to put Canberra back in the contest in the 43rd minute.

Heyman found herself one on one with the keeper on the other side of the break but couldn't convert, and the United skipper was in the thick of things again when she launched a missile from 40 metres out that just went wide.

The hosts were showing signs of life but Van Egmond landed the killer blow with her second goal in the 66th minute.

Garriock rung in the changes but it meant little as Stengel struck in the 80th and 90th minutes to rub salt into the wound.

It was the story of the game - United just missing and Newcastle finding the back of the net, which Heyman says is "just soccer".

Heyman says Canberra were full of confidence at the half-time break but an early goal dented their confidence and gave the Jets an insurmountable lead.

"It's nice to be able to believe in each other and I think that's what we've got now in the squad," Heyman said.

"It was just unlucky and it's always upsetting when things don't fall your way. We just need to get three points [against Brisbane] and just hope on that."

Now Canberra United face an agonising wait to see if they can salvage a finals berth.

NEWCASTLE JETS 5 (Katie Stengel 3, Emily Van Egmond 2) bt CANBERRA UNITED 1 (Ellie Carpenter) at McKellar Park. Crowd 1117.