Central Coast made a stunning start to life under former Matildas boss Alen Stajcic, shocking Newcastle 3-2 in a stoppage-time thriller at McDonald Jones Stadium.
The Jets fought back from 3-0 down to have a chance to equalise in injury time on Saturday when Jonathan Aspropotamitis was deemed to have fouled Roy O'Donovan, whose penalty shot was then saved by Ben Kennedy. Daniel Georgievski scored off the rebound to spark celebrations but VAR then ruled he had encroached into the area early.
O'Donovan was given another chance from the spot and Kennedy again made the stop. It was a dramatic end to an amazing comeback from last-placed Central Coast.
A week after losing 8-2 to Wellington and sacking coach Mike Mulvey, the Mariners dealt the Jets' finals hopes a potentially telling blow by leaving them four points adrift of the top six.
It took the Mariners until the 49th minute to have their first shot but they took a shock lead two minutes later through Jordan Murray. Newcastle-bound Matt Millar produced the through ball for Murray, who placed the one-on-one chance perfectly.
The Mariners doubled the lead in the 64th minute when Millar burst into the Jets' penalty area and produced a cut-back that deflected to Jem Karacan, whose shot went through the hands of Glen Moss. Connor Pain kick-started Mariners celebrations in the 67th minute with a well-placed left-foot strike.
But Newcastle were far from done. They pulled one back in the 74th minute when O'Donovan got a lunging foot to Lachlan Jackson's cross. The Jets were then within sight in the 81st minute when Kennedy failed to handle a shot from Nigel Boogaard. His spill rebounded off Ronny Vargas and into goal for 3-2.
Kaine Sheppard had a golden chance to equalise in the 89th minute but he hit his shot into defender Sam Graham, who was laying on the ground in front of an open goal.