The Sky Blues controlled much of the grand final rematch but it took the intervention of their American signing to break the deadlock with a composed finish on Saturday.

The margin was doubled just before halftime when the Victory knocked the ball into their own net, and while the second half was more even the reigning champions lacked any real potency.

Haley missed Sydney FC's first-round loss due to injury but made her presence felt on debut with a bustling attack on the ball and opposition.

The young forward pounced on a loose pass in the 41st minute and was quickly through on goal, but still had plenty to do after rounding Victory keeper Casey Dumont.

Haley stayed calm even as the Victory defence closed in to finish in the far top corner from a tight angle for a well-deserved opener.

"The two things that caught my eye with Madi is that she holds the ball up and puts people into play, but she's an exceptional finisher too," Sydney FC coach Ante Juric told AAP.

"She works well in our team and she actually fits perfectly with what we do. She'll only get better and better too."

The Sky Blues doubled their lead in first-half stoppage time when Princess Ibini ran to almost the same spot Haley had scored from and crossed the ball.

Dumont looked to have the threat covered but fumbled the ball into defender Kayla Morrison who could only knock the rebound back into the goal.

The Victory created few chances as they slumped to a second consecutive loss.

The defending champions also missed Catherine Zimmerman after the striker was forced from the field in the first half with a leg injury.

"(I was) disappointed with the challenge, to be honest. The girl did get the ball but how we didn't get a free kick out of that was ridiculous," Melbourne Victory coach Jeff Hopkins said.

"The follow-through was what did the damage. She's gone off to hospital for a scan or an X-ray, we'll find out where we go from there, but it's her ankle."

It might have been a more comfortable margin for the Sky Blues if not for some wayward finishing and determined defence from the Victory.

Cortnee Vine set the scene in just the third minute when breaking away to be one-on-one with Dumont but bobbled the ball straight to the Victory keeper.

The Sydney FC speedster impressed until subbed off in the second half, using her pace down the right to regularly get in behind the Victory defence but lacked the polish to make them pay.

The Sky Blues face crosstown rivals Western Sydney Wanderers next with a visit to Marconi Stadium on Saturday, while the Victory host Wellington Phoenix the following day.

Australian Associated Press