Perth Glory opened up a seven-point gap at the top of the A-League with a 2-1 win away to nearest rivals Melbourne Victory.
Tony Popovic's side took a big step towards securing the premiership after taking a two-goal lead in the second half at AAMI Park.
Though Kosta Barbarouses pulled one back with 13 minutes to go the visitors held strong to see off Kevin Muscat's side for the second time this season.
There was controversy over the first Glory goal, scored from the penalty spot by Neil Kilkenny on 61 minutes, but Diego Castro produced an emphatic finish to double their advantage eight minutes later.
Neither side could find a cutting edge in the first half, with Barbarouses firing over and Elvis Kamsoba drawing a save from Perth keeper Liam Reddy.
Ivan Franjic sliced a shot wide for the visitors and they twice went close just before the break. First Chris Ikonomidis shot into the side netting, before Kenny Athiu had an effort blocked from close range.
Victory keeper Lawrence Thomas did well to palm away an effort from Castro just before the hour mark, with Perth then taking the lead.
Kilkenny's flicked pass into the penalty area struck the hand of full-back Corey Brown and he stepped up to convert the spot-kick.
Ikonomidis set up the second goal for Castro, his cross being volleyed past Thomas to put the Glory firmly in the driving seat.
Though Victory had Keisuke Honda making his return from a niggling hamstring injury they couldn't find a way back although Barbarouses' goal from Leigh Broxham's reverse pass made for a tense finish.
The Victory are 9/4 to win the Grand Final, with Perth priced at 15/8.
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