Goals from Archie Thompson, James Troisi and Guilherme Finkler in the first half and Mark Milligan's spot kick after the break saw the visitors romp to a comprehensive win at Westpac Stadium, with Jeremy Brockie's stunning late volley nothing more than a consolation for the demoralised home team.
With Adelaide United having lost away to the Newcastle Jets on Friday night, the result saw Victory climb into the top two ahead of Western Sydney and Central Coast's matches on the road at Melbourne Heart and Brisbane Roar respectively later in the day.
Regardless of the outcome of those games, Kevin Muscat's team are unable to finish lower than fourth and guaranteed at least a home elimination final.
Victory, bearing little resemblance to the lacklustre team who stumbled their way to a 2-2 draw in Newcastle last weekend, began the match at a furious tempo and went ahead inside the first minute.
Troisi exchanged a sharp one-two with Finkler, receiving the playmaker's flicked return pass to burst into the penalty area and find Thompson with a square delivery, the veteran forward slamming the ball home from close range.
The visitors doubled their lead in the 29th minute, with Troisi turning from provider to finisher. He did it all himself too, racing into the penalty area and advancing on goal. The man on loan from Atalanta looked up as if to try and pick out a team-mate, instead unleashing a vicious strike into the roof of the net, leaving Phoenix goalkeeper Jacob Spoonley with no chance.
The hosts were not without their opportunities in the first half. Michael Boxall and Tyler Boyd both saw half-chances go begging, while Nathan Coe, Nick Ansell and Adrian Leijer were all called upon to make important interceptions in dangerous areas.
Ernie Merrick's men were left to rue those missed openings when Victory made it 3-0 on the stroke of half-time. It was a well-worked team move that created the goal, which started when Adama Traore passed to the feet of Kosta Barbarouses on the edge of the penalty area.
The New Zealand international released Finkler into the penalty area, and the Brazilian, played just on side by the Phoenix defence, slipped a cool finish beyond the reach of Spoonley.
Phoenix started the second half better, keeping the ball but failing to carve out a genuine chance. They were punished again a minute before the hour mark when Troisi, galloping into the area, took out three defenders with a smart lofted pass.
Barbarouses arrived to put away what was a simple chance, only to be scythed down from behind by Shaun Timmins. The defender could have no complaints when he was shown a straight red card, and Mark Milligan made no mistake in dispatching the penalty.
While the Phoenix admittedly offered little resistance, it was one of Victory's best performances of the season, and will give them plenty of confidence going into the finals. Not even Brockie's remarkable injury-time effort, a blistering volley at the back post from a corner, could dull the spirits of the away team and their small contingent of travelling fans.
