Melbourne Victory replaced Adelaide United at the top of the A-League ladder on the back of a Nick Ward header at Telstra Dome.
The Victory won Tuesday night's match 1-0 in front of one of the biggest crowds of the season, 27,196.
Ward scored the goal in the 58th minute to give Melbourne their third win over Adelaide in as many clashes this season.
It was midfielder Ward's second goal in three matches and repaid coach Ernie Merrick for putting him in the starting XI for just the second time this season.
The result put the Victory two points clear of their defeated opponents at the head of the table, after wins in their past three games, all at home.
But Adelaide still have four games left to play, compared to Melbourne's three.
The Victory looked the side more likely to score for most of the match, making a succession of attacking moves in the opening minutes.
United keeper Eugene Galekovic was forced to make saves in the sixth and seventh minutes as Matthew Kemp and Danny Allsopp fired in shots.
In contrast, Adelaide's forays forward were restricted to occasional counter-attacks and the visitors did not have a shot on target in the first half.
It was a similar story early in the second half, with Ward's goal capping a sustained period of attack from the Victory.
The goal came from Melbourne's second corner in two minutes, the first of which came when Galekovic produced a stunning save to keep out a ripping Carlos Hernandez free kick from just outside the box.
From the second corner, Billy Celeski's delivery found Ward at the near post and he headed it into the middle of the net.
The goal sparked a strong response from Adelaide, who put the Melbourne defence under plenty of pressure in the next few minutes.
The closest shave for Melbourne was in the 64th minute, when Adelaide striker Cristiano managed to get behind the defence and take on Victory keeper Michael Theoklitos one-on-one.
A desperate Theoklitos made just enough contact on Cristiano's close range shot to deflect it over the crossbar.