A stoppage-time goal from Chris Ikonomidis secured a thrilling 3-2 win for Glory over reigning champions Melbourne Victory in Sunday's Round Two clash at AAMI Park.
Strikes from Joel Chianese and Andy Keogh had put the visitors 2-0 up at the break, before the hosts replied early in the second period through Terry Antonis.
Victory then looked to set to claim a point when Storm Roux headed in from a Keisuke Honda's corner with just three minutes remaining, but deep into stoppage-time, Ikonomidis rounded off a rapid Glory counter-attack by rifling home his first goal for the club from just inside the box.
The win, Glory's first over the navy-and-whites away from home since 2013, moved Tony Popovic's men into second spot on the embryonic Hyundai A-League ladder and left the Head Coach unsurprisingly thrilled.
"It’s a special win for the whole club ... the way we’ve achieved it,” he told Fox Sports.
“I’m delighted with the win. Obviously everyone knows its a tough place to come.
"They’re the champions and are for a reason. Hopefully it’s a real step forward.”
Victory started the brighter, but still found themselves trailing after eight minutes when Jason Davidson's cross from the left was inadvertently deflected goalward by Antonis and Chianese gleefully thumped home his fourth goal for the club from point-blank range.
And 1-0 became 2-0 15 minutes later when Corey Brown's clearance was headed straight back into the box by the diving Tomi Mrcela and Keogh, having been left unattended by the Victory defence, calmly lifted the ball over the advancing Thomas and into the net.
A couple of half-chances for Kosta Barbarouses were all that Victory could muster over the course of the rest of the first half, but it was a different story after the break.
Barely two minutes had elapsed when Honda found Antonis in a pocket of space on the edge of the box and he drilled a low shot past Liam Reddy via the foot of the far post.
With their tails up, Kevin Muscat's men flooded forward, Barbarouses being denied by Reddy after latching on to Honda's dinked ball into the box and the Japanese international then drawing an even better stop from the Glory 'keeper with a fierce strike from outside the area.
Reddy was again called into action to foil the dangerous Barbarouses as the final whistle loomed, but from the resulting corner, Roux came back to haunt his former club by steering home a header.
Yet it was Ikonomidis and Glory who were to have the last word, the Socceroo forward pouncing to ram home the loose ball after Chianese's initial shot had been blocked by Lawrence Thomas.
Melbourne Victory 2 (Antonis 47', Roux 87') Perth Glory 3 (Chianese 8', Keogh 23', Ikonomidis 90+3')
Referee: Jonathan Barreiro
Melbourne Victory: 20.Lawrence THOMAS (gk), 2.Storm ROUX, 3.Corey BROWN, 4.Keisuke HONDA (c), 5.Georg NIEDERMEIER (14.Thomas DENG 75'), 7.Kenny ATHIU (23.Jai INGHAM 57'), 8.Terry ANTONIS, 9.Kosta BARBAROUSES, 10.James TROISI, 15.Raul BAENA (21.Carl VALERI 80'), 22.Nick ANSELL
Substitutes not used: 1.Matt ACTON (gk), 6.Leigh BROXHAM
Yellow cards: Thomas, Honda
Red cards: None
Perth Glory: 33.Liam REDDY (gk), 2.Alex GRANT, 3.Jason DAVIDSON, 4.Shane LOWRY, 5.Ivan FRANJIC (23.Scott NEVILLE 81'), 7.Joel CHIANESE, 9.Andy KEOGH (c) (22.Fabio FERREIRA 78'), 16.Tomislav MRCELA, 19.Chris IKONOMIDIS, 27.JUANDE, 88.Neil KILKENNY (15.Brandon WILSON 88')
Substitutes not used: 1.Tando VELAPHI (gk), 20.Jake BRIMMER
Yellow cards: Kilkenny, Reddy, Juande
Red cards: None