Sydney FC beat minor premiers Perth Glory for the second time this season and closed in on second spot when they won 1-0 at Jubilee Oval.
The Sky Blues picked up a fifth victory in seven games to move five points clear of third-placed Melbourne Victory.
The performance was not the big statement Sydney FC fans had hoped for ahead of the Finals Series, and the only goal of the game won't make any highlight reels of 2018/19.
But Adam le Fondre's 16th goal of his first campaign for the Sky Blues was enough to down the visitors as they suffered just their third loss of the season.
The Glory made six changes to their squad and left five of their first team regulars at home.
Coach Tony Popovic handed his 17-year-old son Kristian his debut off the bench in the second half, and he came closest to a goal when his long-range shot threatened to drop into the net.
Perth weren't able to fashion a shot on goal, but neither did the hosts pose much of a threat up front.
The goal came eight minutes before the break, when a well-weighted Anthony Caceres cross found Paulo Retre at the far post and his header was deflected into lap of le Fondre standing on the goal line.
It was an unmissable chance, and gave him his first A-League goal in seven weeks.
The Sky Blues almost doubled their lead five minutes into the second half when le Fondre slipped a pass through Perth's defence to find Retre but the fullback could only find the side netting.
That miss was nearly punished moments later when Fabio Ferreira missed the target with a half-volley against his former team.
Meanwhile, Brisbane Roar are 7/2 to beat Newcastle on Saturday. The Jets are 7/10, while the draw is 16/5.
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