The Mariners went a goal down in the first half to the Newcastle Jets via winger James Virgili but were able to peg back the deficit through first team regular Nigel Boogaard in the 56th minute.
Matthew Osman put the Mariners ahead with a lovely volley just seven minutes later and the score remained that way until the final whistle.
The win sees the Mariners go to fifth place on the table, only behind fourth-placed Perth Glory on goal difference whilst the Jets are languishing on the bottom.
Adelaide United scored an easy victory over Perth in hot conditions at Hindmarsh Stadium.
Francesco Monterosso scored a superb hat-trick to deny the glory any chance of grabbing an away point.
The gun striker scored in the 1st, 46th and 50th minutes to take his tally 11 goals which puts him on top of the goal scorers table.
Adelaide are now outright second on the table, four points in arrears of Sydney FC.
The visiting Victory skipped away to a three-goal lead thanks to a brace from Nathan Elasi and a 51st minute strike by Dimitri Hatzimouratis before Chris Payne got one back six minutes later.
Brendan Gan sent a scare through the Victory camp when he netted in the 66th minute, shortening the deficit to one but they were able to hold on for a well-deserved three points.
The Victory move to within striking distance of the top four whilst the Sky Blues remain comfortably ahead at the top of the table.
Third-placed Queensland Roar had the bye in Round 19.