Breaking a run of 364 minutes without scoring when Aydan Hammond cancelled out Luka Jovanovic's 31st-minute opener, the Wanderers suffered a late dagger when Jonny Yull came off the bench and won the game in the 93rd minute after Austin Ayoubi and Brandon Borrello had exchanged goals.
The visitors outshot the Reds 26 to nine at Coopers Stadium on Saturday night but struggled to create good chances, with former A-League striker Roy O'Donovan describing their decision-making as "awful" at halftime on the Paramount broadcast.
Denied their own late goal when Joshua Smits produced an incredible fingertip save to deny Bozhidar Kraev in the 83rd minute, the Wanderers will enter their New Year's Day derby against Macarthur bottom of the league if Central Coast pick up a point against Brisbane the day before.
After entering the campaign with aspirations of silverware, Saturday's result heaps further pressure on Stajcic and his side, but the coach insists results will turn.
"We could have won the game," Stajcic told Paramount.
"But we didn't (and) there's nothing you can do. You can't cry over spilt milk.
"We know we can be a challenger for this title, despite where we are on the ladder at the moment.
"I still think we're one of the best teams in the comp.
"(The) points don't show that... (but) if we keep playing like that, I'm sure it'll come."
Jumping into fourth, Airton Andrioli's Reds only produced a single shot on target across the opening half but Craig Goodwin's perfect crossfield pass and Yaya Dukuly's patience to lure in defender Alex Bonetig before finding Jovanovic ensured it gave them the lead.
The visitor's persistence finally paid off when Hammond fired in a 55th-minute attempt that careened in off Vinko Stanisic, only for Ayoubi to restore the host's advantage when he met a Goodwin corner in the 67th.
Stanisic scythed down Angus Thurgate and Borrello converted the resulting penalty moments later to set up a grandstand finish.
But Smits' incredible denial of Kraev ensured Yull was the one to put his name up in lights and send the sold-out crowd into raptures
"When we made it 3-2, (Coopers) was exploding," the Dutch keeper told Paramount.
"This (atmosphere) is similar to Europe."
