Goals from Richard Garcia and Nebojsa Marinkovic sealed another three points for Glory – the club's sixth win from the last seven games – to keep Kenny Lowe's side at the top of the table after 10 rounds.
Adding salt to Newcastle's wounds, captain Kew Jaliens was sent off for a crude tackle on Scott Jamieson late in the match.
Garcia opened the scoring in the 11th minute, firing home his first goal for Perth after a pass from Mitch Nicholls had been deflected into his path.
David Carney spurned a golden chance to equalise early in the second half, but Newcastle never looked like scoring thereafter and Marinkovic wrapped up victory for the hosts with four minutes remaining following good work from Andy Keogh.
In Friday's other game, a wonderful strike from Henrique secured a 1-0 win for Brisbane Roar at Adelaide United.
Henrique cut in from the left in the 18th minute and curled a shot in off the far post to leave Eugene Galekovic with no chance.
Adelaide were unable to respond as they went down to a first defeat at home in 371 days, their previous setback having also come against the Roar.
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