After finishing bottom of the table last season, they did better this season, taking advantage of Brisbane Roar‘s loss to Sydney FC earlier in the to end the season in third place.
With the Central Coast Stadium full cheering supporters, the hosts set about making the most of the chance given them by Sydney FC.
They began the better side of the day and took control of the tie in the 25th minute through Jack Clisby. The centre back was the unlikely scorer of his side’s first goal, as he took advantage of a loose ball in the penalty area to volley home after United had failed to clear a corner.
The goal was all that separated both teams in a first half that saw the home team record two shots on goal and a total of 12 attempts between them.
But after an uneventful first half, the visitors emerged from the break the better of the two teams.
They put their hosts under pressure and could have equalised early in the second half, but goalkeeper Mark Birighitti in the Mariners goal was on hand to them with several key blocks.
With five minutes left of the clock, Marco Urena, who had been rested for the final series, came off the bench to net the Mariners’ second and seal three points for the hosts.
Mariners will host Macarthur next Saturday in the first semifinal, while Brisbane Roar will play Adelaide United the day after.