A goal in each half has seen Sydney outlast Melbourne Victory to secure the W-League premiership in a winner-takes-all contest at Cromer Park.

Teresa Polias netted with a superb strike just on the half-hour mark and Princess Ibini tucked home a penalty midway through the second half to virtually end the contest.

Victory gave the Sky Blues a late scare with a goal from Kyra Cooney-Cross deep into added time, but it was too little too late for the Melbourne side.

The 2-1 victory secured a first premiership in a decade for three-time champions Sydney.

The win pushed the Sky Blues three points clear at the summit at the end of a 12-match campaign and sets up an Easter weekend semifinal against Canberra United.

Melbourne Victory, who were chasing a win to leapfrog Sydney into top spot, finished in third place and now face a match-up against runners-up Brisbane Roar.

The two teams were evenly matched for long periods on the artificial surface on Sydney's northern beaches, before Polias's high-quality strike on 29 minutes broke the deadlock.

The Sky Blues benefited from a softly awarded free-kick on the edge of the penalty area and Polias duly exacted full toll.

The defensive midfielder chose the perfect time to fire in a sweetly hit shot around the wall for just her third goal in 156 W-League appearances.

Visiting goalkeeper Gaby Garton made a barely believable point-blank block from Remy Siemsen just after halftime as the home side resumed the contest with added zest.

Victory star forward Lisa De Vanna enjoyed a couple of bright moments in attack but was largely contained by an injury-hit Sydney FC backline.

Victory gifted Sydney their second on 73 minutes with an unnecessary foul inside the penalty area on Sky Blues leading scorer Siemsen.

Ibini stepped up and coolly tucked home the spot-kick leaving the Victory with an uphill task as the rain started to fall.

With one eye on the weekend semifinal, Victory coach Jeff Hopkins took off a trio of key personnel in Annalie Longo, Amy Jackson and De Vanna before midfielder Cooney-Cross netted with a stunning strike from an acute angle with virtually the last kick of the match.