The point the Melbourne Knights took away from Hamilton for their 2-2 draw with the Football Kingz proved to be a telling factor at the end of the seventh round.
The Knights, one of three unbeaten teams at the start of the round, emerged as the only sidewith an unblemished record after losses were sustained by the previous leaders, the Olympic Sharks and Adelaide City Force.
In an amazing game, South Melbourne upset the Sharks 6-4 at home.
All Whites striker Vaughan Coveny scored twice for the winners, including a penalty in the last minute.
Adelaide lost 2-1 at Newcastle, although they led 1-0 at halftime.
The Brisbane Strikers continue to struggle, beaten 4-1 at home by the Marconi Stallions who pushed the Queenslanders to the place that they had occupied at the bottom of the table.
For Marconi coach Raul Blanco it was his first win of the season. Joe Spiteri, in his first match for the club, scored twice.
Perth Glory shrugged off the difficulties of an away trip to Sydney to beat Northern Spirit 3-1 and go to the top of the table.
Sydney United downed the Wollongong Wolves 2-1.
With Perth having the bye this week, Olympic Sharks have a chance of regaining the top spot with a home game against Sydney United.
