Harrison Sawyer's goal inside the opening minute put Macarthur in front at Campbelltown Stadium, while the Wanderers were contentiously denied a handball penalty five minutes later.
The Bulls looked sharper from the opening minutes but Western Sydney came out of the half-time break with fresh intent and drive and deserved an equaliser before Pantazopoulos struck in the 82nd minute.
Wanderers coach Alen Stajcic dropped veteran midfielder Josh Brillante and started striker Alou Kuol, attempting to add further attacking punch.
Bulls recruit Anthony Caceres, back playing alongside Luke Brattan in midfield, was excellent.
Mile Sterjovski's Macarthur took the lead when Callum Talbot dropped a wonderful floating cross onto the head of Sawyer, who rose to head home.
WHAT A START - A goal within 90 seconds 😲⚡�— Isuzu UTE A-League (@aleaguemen) November 1, 2025Harrison Sawyer heads home to get @mfcbulls off to the perfect start against the Wanderers 🔥Watch #MACvWSW live on 10 Drama, and stream live on Paramount+ 📺 pic.twitter.com/8KWasAZ4X6
The Wanderers felt they deserved a handball penalty in the sixth minute, after the ball struck Sawyer's hand in the area, but it was waved away.
In the 20th minute, Kosta Barbarouses lashed onto a ball from Bozhidar Kraev and went on a mazy run but dragged his shot wide.
Kraev put a shot over the bar in the 37th minute as the Wanderers started to build into the game.
The Wanderers peppered early in the second half without reward.
VAR looked at a clearance from Bulls defender Damien Da Silva for a potential handball but it was ruled a header.
Western Sydney kept pressing and Bulls goalkeeper Filip Kurto denied Alex Bonetig's header towards the far post in the 74th minute, while Macarthur midfielder Liam Rose limped off in the 77th minute.
82' | GET INNNNN PANTAZOPOULOS HEADS IN AT THE BACK POST!— WS Wanderers FC (@wswanderersfc) November 1, 2025⚫� 1-1 ⚪� | #WSW #MACvWSW pic.twitter.com/on9AGGfQu6
The Wanderers finally broke through when Barbarouses got past Da Silva and whipped a wonderful ball to the back post, where Pantazopoulos steamed in to equalise with a bullet header.
Kurto denied Aydan Hammond in injury time and the Bulls defence held on for dear life as Brandon Borrello attacked relentlessly, to keep a point.
The Bulls (1-1-1) return to ACL 2 action at home to Vietnamese club Cong An Hanoi FC on Thursday then play Sydney FC three days later, while winless Western Sydney (0-2-1) travel to face Adelaide on Friday night.