Venue: Hindmarsh Stadium
The Reds started well early but big striker Lloyd Owusu could not even get his shot on target after Travis Dodd played him through, his shot from the top of the box completely missing.
In the 11th minute, Cassio made a brilliant run down the left side and crossed in for Dodd who also seemed to have the yips and somehow managed to miss from right on the line before Mariners defenders swooped and were able to keep out any follow-ups before the linesman called for off-side.
The Reds were peppering the Mariners goal with plenty of forward forays and finally got their reward in the 33rd minute when Cassio curled a free-kick into the top left corner from 25 yards with that Mariners keeper Danny Vukovic could only get a hand to.
The second half ebbed and flowed with the Mariners attempting to get themselves back into the contest but it was almost out of their reach in the 67th minute when Dodd made a blinding run through the midfield only for his shot from the edge of the area to go wide of the mark.
The Mariners tried in vain to net an equaliser but Adelaide were able to hold them out and record a much-needed win.