A dull first half gave little hint of what was to come after the break, with Jean Carlos Solorzano's first league goal in three years the only moment of note before the interval.
The game burst into life around the hour mark as Eddy Bosnar and Matt Simon struck inside seven minutes of each other to put the hosts ahead.
James Donachie levelled matters, but substitute Kim Seung-yong looked to have won it for the home side when he struck 10 minutes from time.
However, the Mariners could only hold the lead for two minutes before Solorzano got his second to ensure the visitors escaped with a point.
Elsewhere, Melbourne Victory were indebted to Guilherme's 85th-minute strike in a 1-0 triumph over lowly Newcastle Jets.
Victory, who lost to their city rivals last time out, bounced back to move second in the table.
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