A brilliant first-half show from star recruit Ryan Fraser had helped the Wanderers build a two-goal lead before halftime in the bottom-two clash at CommBank Stadium on Friday.
But the 'Nix emerged the better side after the break, desperate to snap a three-game losing streak and avoid finishing the round dead last in 12th.
Incensed after a failed bid for a penalty kick in the 59th minute, Bill Tuiloma opened Wellington's account in the 68th after a corner kick.
Wanderers centre-back Jacob Farrell had brought down an airborne Matthew Sheridan in the box, but escaped giving away a costly penalty.
'Nix forward Ifeanyi Eze then beat goalkeeper Lawrence Thomas to level the scores in the 72nd minute, with the Wanderers unable to restore their lead despite 11 minutes of added time.
Giancarlo Italiano's Wellington rise to 10th ahead of the weekend's matches, three points behind sixth-placed Adelaide (23).
Only seven points separate the Newcastle-led top six, with nine home-and-away rounds remaining.
"It's normal to be frustrated. We're playing for our season," Italiano said.
"I thought it was a foul (from Farrell). Matthew doesn't play the referee, look for fouls.
"He's the most honest player that you can coach, so the fact that he went down, I know that here must have been some contact."
Meanwhile, Western Sydney remain last in the league on 17 points after their fourth match under new coach Gary van Egmond.
A concussion to star striker Bozhidar Kraev only adds to Western Sydney's woes.
Kraev was substituted off in the 79th minute after a clash of heads with Wellington midfielder Kazuki Nagasawa.
"It feels more than a loss than you're gaining a point," van Egmond said.
"There's a bit of belief in regards to this team that we're going to have to work on."
Fraser was at the source of Western Sydney's best chances and found the 17th-minute opener on the counter-attack, curling the ball home after a long ball from teammate Dylan Scicluna.
It was Fraser's third goal in four matches, with Phillip Cancar adding to the lead in the 43rd minute.
The Phoenix could only manage three shots in the first half, with Armiento and Singh leading the attack.
Singh was later forced out of the match in the 55th minute with a left knee injury.
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