Perth Glory tasted defeat on the road for the first time this season as Adam Le Fondre's first-half goal proved enough to secure all three points for Sydney FC at Netstrata Jubilee Stadium.
A much-changed Glory side matched the Sky Blues for long periods, but despite mounting a concerted late rally, were ultimately unable to find a response to the English striker's 16th goal of the season.
Nevertheless, Head Coach Tony Popovic felt that there were plenty of positives to be taken from the game.
"Overall it was a good performance," he told Fox Sports.
"We've come away from home and I thought we controlled large parts of the game and they tried to get us on the break.
"We had some good chances there at the end and I thought the players did themselves proud.
"We got some minutes into players and we want everyone fit and available for the finals.
"It wasn't the result we desired, but there were some very good passages of play from us."
The opening half-hour was light on clear-cut chances for either side, with Glory's most threatening moments both provided by Brendon Santalab who was narrowly off-target with a header and a fizzing, 25m shot.
But on 37 minutes, the Sky Blues hit the front with what was effectively their first sight of goal.
Anthony Caceres got away down the left before standing up a cross which Paulo Retre nodded back across the face of goal and the predatory Le Fondre was on hand to nudge the ball over the line from point-blank range.
Retre then found the side-netting with an angled strike as the game opened up early in the second half and moments later, at the other end, Fabio Ferreira was just unable to steer his volley from the edge of the box on target.
A trademark Shane Lowry block prevented Josh Brillante's fierce shot from troubling Liam Reddy on the hour-mark, before the Glory 'keeper was called into action to keep out Rhyan Grant's effort.
As the game moved into its final quarter, 17-year-old Kristian Popovic was handed his senior debut from the bench and there was also a first appearance of the season for Chris Harold.
And it was Glory who proceeded to dominate the latter stages, with the Sydney FC defence stretched to breaking point to keep them at bay.
Half-chances fell the way of Harold, Popovic and fellow-substitute Diego Castro in a frantic finale, but the men in white were just unable to find a way through.
Sydney FC 1 (Le Fondre 37') Perth Glory 0
Referee: Chris Beath
Sydney FC: 1.Andrew REDMAYNE (gk), 2.Aaron CALVER, 4.Alex WILKINSON, 6.Josh BRILLANTE, 8.Paulo RETRE, 9.Adam LE FONDRE (18. Jacob TRATT 90+4'), 10.Milos NINKOVIC,13.Brandon O’NEILL, 17.Anthony CACERES (11.Danny DE SILVA 84'), 22.Siem DE JONG (16.Reza GHOOCHANNEJHAD 72'), 23.Rhyan GRANT
Substitutes not used: 20.Alex CISAK (gk), 21. Mitch AUSTIN
Yellow cards: None
Red cards: None
Perth Glory: 33.Liam REDDY (gk), 4.Shane LOWRY, 5.Ivan FRANJIC, 7.Joel CHIANESE, 11.Brendon SANTALAB, 16.Tomislav MRCELA, 20.Jake BRIMMER (29.Kristian POPOVIC 75'), 21.Jacob ITALIANO (17.Diego CASTRO 46'), 22.Fabio FERREIRA (14.Chris HAROLD 72'), 23.Scott NEVILLE, 88.Neil KILKENNY
Substitutes not used: 1.Tando VELAPHI (gk), 15.Brandon WILSON
Yellow cards: Franjic, Santalab
Red cards: None