Glory's unbeaten start to the season was finally ended on Friday evening as Sydney FC ran out 2-1 winners in sweltering conditions at nib Stadium.
Adam le Fondre's instinctive finish gave Steve Corica's side the lead in the first half, before former Glory man Danny De Silva made it 2-0 late in the second.
Chris Inkonomidis duly bagged his sixth goal of the campaign to set up a grandstand finish, but it wasn't quite to be for Tony Popovic's men.
Despite the defeat, Glory remain two points clear at the top of the Hyundai A-League and while naturally disappointed by the result, Popovic was quick to praise his charges' resilience.
"The last five minutes showcased the spirit of the team," he said.
"Even when you feel all is lost, the players still show their fight, determination and character and in the end, we could have had an equaliser.
"It epitomises what the players have done through the first nine games of the season.
"We'll get over this. We've lost a game of football. I think in the first 20 minutes, the growth of the team was evident as we totally dominated the game.
"But as the game shows you, you can get kicked at those times and we conceded a goal out of nothing and they played as a team with experience that is very accustomed to winning and it became hard for us to break them down.
"I'm certainly not happy that we lost and we played well enough for the [unbeaten] run to have continued tonight.
"It wasn't to be, but there's not too much wrong. We just need to recover well, enjoy Christmas with our families and come back to start the next series of games, in what is a very busy period in January, refreshed and ready to go."
Having enjoyed the ascendancy for the opening 15 minutes, Glory were stung when a Brandon O'Neill corner fell at the feet of le Fondre and he pounced to hook home his seventh goal of the season.
It took some inspired goalkeeping for the Sky Blues to maintain their lead on the half-hour mark, however, Andrew Redmayne foiling Andy Keogh at point-blank range after the Irishman had met Ivan Franjic's cross with a fierce, low strike.
Liam Reddy than matched his counterpart in first-half stoppage-time, somehow managing to parry Alex Brosque's effort from inside the six-yard box.
Glory began the second half on the front foot, Jake Brimmer almost immediately forcing Redmayne into action with a well-struck free-kick and they continued to press hard for an equaliser as the half progressed.
And yet, just as they had done before the break, the NSW side managed to find a way through, Milos Ninkovic's pass picking out De Silva who applied a composed finish.
To their credit, the home side refused to roll over and halved the arrears as the clock ticked past the 90-minute mark when Dino Djulbic headed Neil Kilkenny's corner back across goal and Ikonomidis materialised at the far post to beat Redmayne.
Sensing a dramatic comeback was on the cards, The Shed raised the decibel level and many thought Glory had snatched a point when substitute Brendon Santalab fired into the net from just inside the box, but the effort was ruled out due to Joel Chianese's earlier foul on Redmayne.
Perth Glory 1 (Ikonomidis 90') Sydney FC 1 (le Fondre 18', De Silva 85')
nib Stadium, Perth
Referee: Jonathan Barreiro
Perth Glory: 33.Liam REDDY (gk), 3.Jason DAVIDSON, 4.Shane LOWRY, 5.Ivan FRANJIC (7.Joel CHIANESE 60', 6.Dino DJULBIC, 9.Andy KEOGH (11.Brendon SANTALAB 67'), 16.Tomislav MRCELA, 19.Chris IKONOMIDIS, 20.Jake BRIMMER, 27.JUANDE (23.Scott NEVILLE 79'), 88.Neil KILKENNY
Substitutes not used: 1.Tando VELAPHI (gk), 15.Brandon WILSON
Yellow cards: Franjic, Juande, Lowry
Red cards: None
Sydney FC: 1.Andrew REDMAYNE (gk), 2.Aaron CALVER, 4.Alex WILKINSON, 6.Josh BRILLANTE, 7.Michael ZULLO (18.Jacob TRATT 90'), 9.Adam LE FONDRE, 10.Milos NINKOVIC, 13.Brandon O’NEILL, 14.Alex BROSQUE (c) (11.Daniel DE SILVA 83'), 22.Siem DE JONG (8.Paulo RETRE 60'), 23.Rhyan GRANT
Substitutes not used: 20.Alex CISAK (gk)
Yellow cards: Brosque, Retre
Red cards: Nil