A well-taken first-half goal from Joel Chianese proved enough to secure Glory a hard-fought victory over Wellington Phoenix in a pulsating Elimination Final at Bankwest Stadium.
The 30-year-old found the bottom corner in the 18th minute and Tony Popovic's men then held firm in the face of a late onslaught from the Kiwi side to set up a Grand Final rematch with Sydney FC in Wednesday's Semi-Finals.
In a breathless game littered with chances at either end, Liam Reddy produced several key saves to preserve Glory's lead, notably from Ulises Davila just before the break, while David Ball struck the woodwork as Phoenix maintained their desperate search for an equaliser right up to the final whistle.
Unsurprisingly, Popovic was quick to hail his side's character in his post-match comments.
"It was a fantastic defensive display," he said.
"We lost Alex Grant to an ankle injury in training yesterday, unfortunately, so we had to readjust the line-up and I thought the players were excellent.
"It was everything you could ask for from a playing group in a Finals game and I think that just shows the belief the players have had throughout this whole hub.
"Results aside, I've always believed in these players and what they showed today may surprise many people outside the hub, but certainly no-one within the hub.
"Now we focus on Sydney FC.
"You have to beat the best to win the Championship and they've been the best this year, so we know what we're up against.
"But we're a game away from the Grand Final, so we'll go and give it everything we have, as we did tonight and we know we're a chance."
Any notion of a cagey Finals contest unfolding was dispelled as early as the second minute when Tomislav Mrcela rose highest to meet Neil Kilkenny's inswinging free-kick but couldn't keep his header down.
And it was from another Kilkenny corner soon that Glory came agonisingly close to opening the scoring, Bruno Fornaroli trying to force the loose ball over the line, Stefan Marinovic somehow managing to push the Uruguayan's effort onto the bar and David Ball clearing Chianese's follow-up effort off the line.
Glory and Chianese were not to be denied moments later, however, Jake Brimmer's pinpoint through-ball releasing the pacy attacker who showed no hesitation in bagging his fifth goal of the season with a crisp left-foot strike.
Stung by that setback, Phoenix proceeded to test out the Glory defence and they found Reddy in fine form.
The man who starred for Wellington when they defeated Glory on penalties in the 2010 Finals produced a smart stop at the near post to foil Jaushua Sotirio, before repeating the feat to keep out both a free-kick and a 20m strike from Davila.
Ivan Franjic then did well to block Liberato Cacace's goalbound effort right at the start of the second half ahead of another strike from Davila which drew a regulation save from Reddy.
Piscopo was next to try his luck for Phoenix, fizzing a shot narrowly wide from just outside the box and it was the lively attacking midfielder's free-kick that was volleyed over by Steven Taylor seconds later.
Reddy was called into action once again in the 70th minute, getting down well to keep out Sotirio's shot across the face of goal and the Wellington forward threatened again almost immediately, contriving to blaze wide from 10m out having been teed up by Callan Elliot.
The Glory 'keeper continued to excel, blocking Ball's angled shot and yet another long-distance effort from Davila, before Ball struck the top of the bar with a hooked volley in what proved to be the final chance of a memorable encounter.
Hyundai A-League 2020 Elimination Final 1
Wellington Phoenix 0 Perth Glory 1 (Chianese 18')
Bankwest Stadium, Parramatta
Referee: Alex King
Assistant Referee 1: Owen Goldrick
Assistant Referee 2: James Cleal
Fourth Official: Kurt Ams
VAR: Kris Griffiths-Jones
Wellington Phoenix: 1.Stefan MARINOVIC (gk), 4.Te Atawhai HUDSON-WIHONGI, 5.Matti STEINMANN (14.Alex RUFER 86'), 7.Reno PISCOPO, 8.Cameron DEVLIN (21.Callum McCOWATT 74'), 9.David BALL, 10.Ulises DAVILA, 11.Jaushua SOTIRIO, 13.Liberato CACACE, 17.Callan ELLIOT, 27.Steven TAYLOR (c)
Substitutes not used: 2.Liam McGING, 12.Brandon WILSON, 30.Zac JONES (gk), 31.Ben WAINE, 32.Sam SUTTON
Yellow Cards: Devlin
Red Cards: None
Perth Glory : 33.Liam REDDY (gk), 5.Ivan FRANJIC, 7.Joel CHIANESE, 9.Bruno FORNAROLI (c), 16.Tomislav MRCELA, 20.Jake BRIMMER (22.Vince LIA 87'), 21.Tarek ELRICH, 23.Dane INGHAM, 27.JUANDE, 29.Kristian POPOVIC (13.Osama MALIK 80'), 88.Neil KILKENNY
Substitutes not used: 8.James MEREDITH, 25.Carlo ARMIENTO, 28.Gabriel POPOVIC, 50.Daniel MARGUSH (gk), 61.Yianni PERKATIS
Yellow Cards: Mrcela, Juande
Red Cards: None