Glory were edged out 4-3 on penalties by Newcastle Jets after their Surf City Cup clash finished 1-1 at the Croatian Sports Centre in Carrara.
Ben Kantarovski's header gave the Jets an early lead before Neil Kilkenny levelled things up from the spot on the stroke of half-time.
With neither side able to find a winner in the second-half, a shootout was required to determine who would finish as runners-up to Brisbane Roar in the Surf City Cup.
And with the Jets leading 4-3, Ivan Franjic saw his spot-kick blocked by former Glory man Lewis Italiano, thus handing Ernie Merrick's men the victory.
The WA side created the better chances throughout a lively first half, with Bruno Fornaroli, Chris Harold, Joel Chianese and Diego Castro all going close.
Yet it was Newcastle who struck first, Kantarovski rising highest to meet a Dimi Petratos free-kick and find the net with a powerful header.
Undaunted by that setback, Glory continued to look menacing going forward and finally got their reward in the last minute of the half.
Harold was sent in on goal by a sublime lofted through-ball from Kilkenny and as the striker prepared to pull the trigger, he was hauled down in the box by Italiano.
Kilkenny stepped up to take the penalty and calmly sent Italiano the wrong way as he rifled the ball into the bottom corner.
Both sides made wholesale changes at various points after the break which perhaps contributed to the more disjointed nature of the second half.
The Jets were quicker out of the blocks and came within centimetres of restoring their lead just after the hour-mark when Panamanian import Abdiel Arroyo showed great pace to race clear, only to see his shot strike the foot of the post and rebound away to safety.
Franjic and Chris Ikonomidis, the latter making a welcome return from shoulder surgery, threatened to snatch a late winner for Glory, but it wasn't to be and so, to the surprise of many in the ground, penalties were ordered.
Steven Ugarkovic scored Newcastle's first, but Juande saw his first-up effort for Glory saved, before John Koutroumbis and Jake Brimmer both found the net.
Dimi Petratos then fired wide, allowing Gabriel Popovic to step up and make it 2-2.
The respective Petratos and Popovic siblings, Maki and Kristian, duly scored to move the score to 3-3, but after Kosta Petratos made it 4-3 to Newcastle, Franjic saw his effort saved by Italiano, enabling the Jets to claim the spoils.
Surf City Cup 2019
Perth Glory 1 (Kilkenny (pen) 44') Newcastle Jets 1 (Kantarovski 11')
*Newcastle win 4-3 on penalties
Croatian Sports Centre, Carrara
Perth Glory: 1.Tando VELAPHI (GK), 3.Jacob TRATT, 7.Joel CHIANESE (5.Ivan FRANJIC 46'), 10.Bruno FORNAROLI (28.Gabriel POPOVIC 46'), 12.Soo-beom KIM (25.Ethan BROOKS 65'), 13.Osama MALIK (22.Riley WARLAND 46') (26.Luke BODNAR 85'), 14.Chris HAROLD (19.Chris IKONOMIDIS 65'), 16.Tomislav MRCELA, 17.Diego CASTRO (27.Juande 46'), 29.Kristian POPOVIC, 88.Neil KILKENNY (20.Jake BRIMMER 46')
Substitutes not used: 33.Liam REDDY (GK)
Yellow Cards: Kim
Red Cards: None
Newcastle Jets: 20.Lewis ITALIANO (GK), 3.Jason HOFFMAN, 5.Ben KANTAROVSKI, 6.Steven UGARKOVIC, 8.Wes HOOLAHAN, 9.Abdiel ARROYO, 10.Dimitri PETRATOS, 11.Nick FITZGERALD, 16.Matt MILLAR, 18.John KOUTROUMBIS, 23.Matthew RIDENTON
Substitutes: 19.Kosta PETRATOS, 28.Patrick LANGLOIS, 31.Maki PETRATOS, 40.Noah JAMES (GK), 45.A TRIALIST
Yellow Cards: None
Red Cards: None
Pictures courtesy of Paul Smith