Wellington will be out to stop the A-League's top four from breaking away when they host the last-placed Newcastle Jets on Sunday.
The fifth-placed Phoenix desperately need a win to stay in touch with the top four and keep their dreams of a maiden finals berth alive.
Taking all three points against the Jets will put Wellington one point behind fourth-placed Queensland whereas a loss will open up a four-point buffer with just three rounds remaining.
That would effectively give the Roar, Melbourne, Adelaide and Central Coast a stranglehold on the four finals spots.
Phoenix coach Ricki Herbert knows how important Sunday's Westpac Stadium clash is but has resisted talking up the clash as `do-or-die' to his troops.
"If we can get three points from this then we'll be well in the equation," Herbert said.
"But I'm not putting any added pressure on the players.
"They know what they need to do and everyone's looking forward to this one.
"At this stage we can't look any further down the track than Sunday."
Wellington's cause has been hurt significantly by suspensions to captain Andrew Durante and fellow Australian Jon McKain.
Durante was red-carded during last weekend's 3-2 loss to the Roar in Brisbane, while McKain collected his fifth yellow card of the season in the same match.
In the Phoenix's favour however, is their impressive record at home in recent months, having won three and drawn one of their past four matches at Westpac Stadium.
Herbert said his side was keen to maintain its recent dominance in New Zealand but was expecting a fired-up opponent.
"We've done well at home this season and we need to continue that on Sunday," Herbert said.
"There is always going to be pride from teams irrespective of where they are on the table and I'm sure Newcastle will be like that."
The Jets, reigning A-League champions, are out of finals calculations but still have plenty to play for with the Asian Champions League looming.
Jets coach Gary van Egmond said his side would be out to kill off the Phoenix's finals hopes.
"I feel if we win this weekend against them, it's going to be a real difficult one for them to get to the top four," van Egmond said.
The Jets will display the Leukaemia Foundation logo on their jerseys for the match with New Zealand law preventing them from displaying major sponsor Centrebet's logo.