It's the seventh time the Phoenix have qualified for post season football and surely the most meritorious, given their young squad and the numerous obstacles they've had to overcome.
It's also remarkable given the resources available to much bigger clubs that will miss the cut this season, like Sydney FC.
Sail was again superb but everyone in a Phoenix shirt rose to the occasion, with Ben Waine's shift as a makeshift right wing back typical of the effort.
The Phoenix opened the scoring with a peach of a goal in the fourth minute. David Ball and Ben Old combined to create space, before Ball's cross found Sutton, who volleyed home sweetly from 10 yards. It was Sutton's first goal in his 36-game A League career – and what a time to score.
The Phoenix have been experts at defending leads this season but it was always going to be difficult from such an early junction.
Sutton managed a brilliant block to deny Keijiro Ogawa, when the Japanese looked odds on to score, before Hemed popped up again to torment his former club.
The Israeli striker produced a neat turn and finish in the 29th minute, though he was allowed too much space inside the area, with the Phoenix defence also passive as the move developed.
The equaliser sparked Wellington, who were increasingly dangerous on the counter attack. Another sweet Sutton shot smashed against the crossbar, with Waine fractionally offside as he turned in the rebound.
Just before halftime Gael Sandoval was also unlucky, watching his delicate free kick from the edge of the area hit the bar with the keeper well beaten, the kind of attempt that the Diego Maradona made famous in his Napoli heyday.
Old looked to have scored early in the second half, but his precise volley was chalked off, with Ball judged to be millimetres offside, in one of the frustrating decisions that have become part of the VAR era.
Ball went close again – blazing over from six yards – before Piscopo produced his goal of the season contender, bending a wonderful effort into the far corner from outside the box, after being released by Sandoval on the counter.
That was the impetus for the Wanderers to lift again. Sail produced two stunning interventions – with the first to deny Jarrod Carluccio particularly special - as the Wanderers player met a well-judged cross.
It made for a nervous finale, given what was at stake, with coach Talay booked for time wasting over a substitution at one point, but the Phoenix held strong to take another giant step forward.
Wellington Phoenix 2 (Sam Sutton 4, Reno Piscopo 65)
Western Sydney Wanderers 1 (Tomer Hemed 29)
Halftime 1-1
