Phoenix played one of its finest matches of the season in front of a 10,267 crowd and was never troubled by a disjointed Brisbane side after taking an early lead.
And it did it without the league's leading scorer Nathan Burns, who is on Australia duty for the AFC Asian Cup.
Wellington is now four points behind leader Perth Glory, which faces Adelaide United on Monday.
Brisbane is still seventh with its season going from bad to worse.
Phoenix took the lead after four minutes when fullback Manny Muscat, in an unfamiliar position of left winger, received a through ball from Michael McGlinchey and produced a burst of speed to go past a Brisbane defender and slip the ball into the net past advancing goalkeeper Jamie Young.
Muscat amazingly had another gilt-edged chance a few minutes later when he was expertly put through by McGlinchey but his low shot missed the far post with Young beaten.
Brisbane was finding it hard to cope with Phoenix's hard-working midfield and the home side enjoyed the lion's share of possession although striker Henrique did his best to inject some life in the champion's attack.
Brockie, playing in his last match for Phoenix before moving to South Africa to play for SuperSport, had an opportunity to sign off with a goal when he was served by McGlinchey but his volley was blocked.
McGlinchey was in superb touch in midfield and on 38 minutes he set up Roly Bonevacia but the Dutchman shot wildly over the bar from a promising position.
Moments before half-time he served Vince Lia with a delightfully struck free kick but the midfielder failed to make contact from a metre out.
Brockie got another chance to leave his mark on the game five minutes into the second half when he won a penalty after being upended by Young. This time he would not miss and he sent Young the wrong way with a low shot.
"The ideal scenario would have been to get the three points first and then knock one in the back of the net to top it off," Brockie said afterwards.
Designated penalty-taker Roly Bonevacia had no problem handing the spot-kick over to Brockie..
"I just grabbed the ball, there was not much conversation. He'd been practising them during the week but he asked me if I wanted it and I wasn't going to say 'no'.
"What a way to finish my career at the Phoenix."
On the hour Bonevacia narrowly missed scoring the goal of the season when Rodriguez played a flick pass to the Dutchman who, without letting the ball hit the ground, hit an outrageous volley that went just wide.
Phoenix was flying and there was nothing Brisbane could do to change the course of the match.
Brockie piled more misery on Brisbane in the 66th minute when he took a touch and volleyed home a spectacular goal to put the home side in complete control.
The goals brought Brockie's A-League tally to 39, with 23 coming in the past three seasons for Wellington.
As he celebrated his goal in front of the Yellow Fever, Luke Brattan and Young appeared to be arguing a point.
Young saved Brisbane from more embarrassment when he stopped a fierce drive from Bonevacia six minutes from time.
