If Sydney had salvaged a point from this game, or even done something to suggest they were in same league as Central Coast, fans could have left Sydney Football Stadium with a glimmer of hope.
Sydney's dire performance was well reflected in the demeanour of coach and skipper in the after-match press conference. They both looked ill ... and so they should.
Mariners' Graham Arnold was grumpy too — what's new — but that was just because his team got a little sloppy in the second half after playing with so much discipline that only a miracle would have seen Sydney escape.
Mariners aren't a great side but they demonstrated individually and as a team qualities that Sydney lacks: balance, composure, confidence and purpose.
Sydney's crowd was down since their flogging at the hands of Heart before Christmas. The Cove had worthy adversaries in the Mariners fans at the other end, singing above their numerical weight.
Mariners kicked off and both sides played tentatively with the ball but fiercely without it.
Rhyan Grant — introduced at right back at the expense of Jamie Coyne as part of Vitezslav Lavicka's defensive shake-up — went in hard against Oliver Bozanic, Karol Kisel was fouled by Pedj Bojic and Brett Emerton was fouled.
Grant gave Liam Reddy a hospital pass that must have given Lavicka pause. And Grant was not alone. A solid spell of defensive comedy was only relieved by Mariners conceding a free kick in their eagerness to take advantage.
Sydney struggled to play the ball away from their back line until Terry McFlynn got a pass to Nick Carle, who found Bruno Cazarine. Then Emerton got Grant into the right corner.
Patrick Zwaanswijk sent a good searching ball for Bernie Ibini, who was relishing every pass that came anywhere near him.
Ibini also played a role in Mariners' goal. Pedj Bojic found good space to the right of Sydney's penalty area and crossed, Ibini letting the ball run on to Bozanic, who no-one picked up as he ran in from the top of the box and took his easy chance.
This wasn't against the run of play. Unless the goal fired the home team into action the fans could only expect the Mariners tally to increase.
Joshua Rose was strong down the left but Grant did enough to force a corner.
Sydney continued to have trouble containing Ibini who in the 16th minute got a break on goal requiring Reddy to come out and block. From the corner Zwaanswijk headed over the crossbar.
Joshua Rose, John Hutchinson and Olly Bozanic combined well to win another corner. Ibini played across to Rose who shot over the top left corner of goal.
In the 24th minute Sydney had its first real chance — slight as it was. McFlynn found Kisel who found Carle, whose shot at least gave Matthew Ryan an excuse to familiarise himself with the turf.
Bernie Ibini-Isei was still getting the better of Sebastian Ryall (who might even have been having a worse game than the struggling Grant) and Bozanic was regularly getting away from Emerton.
Thirty minutes in and Sydney were still struggling to get the ball out of their own half. Bozanic, Michael McGlinchey, Mustafa Amini and Hutchinson were shutting down all one-two attempts as Sydney tried to get the ball away from their backline.
It was all pretty dreary until the 39th minute when Carle robbed McGlinchey but Sydney had little to offer once the ball and Carle were separated.
Cazarine wasn't able to get a good first touch on any ball sent to him — partly because the supply was poor and partly because if they got close enough Zwaanswijk spoiled the party. Sydney were trying to win by putting Mariners to sleep. The crowd started jeering.
Emerton and Grant exchanged junk crosses to one another (one of these chaps could find themselves back on the bench and the other would find it hard to make the bench were he not who he is).
Michael Beauchamp did something useful: chasing back to stop Ibini and Daniel McBreen as they entered the Sydney penalty area. But on Mariners' corner Zwaanswijk headed down on goal where Terry Antonis cleared off the line.
At the half time whistle there were boos from the stands — Sydney would have deserved them but they were probably for referee Jarred Gillett.
The two gents to my right thought Sydney were "Pretty bad" and "Terrible, terrible". Would they continue to try to bore Mariners into submission in the second half?
Perhaps a beer would help? Me if not Sydney. A Mariners fan in the beer queue was mighty happy with Ibini and Amini but lamenting their stay would be short-lived.
Sydney came out with a change (Cazarine gone for Mark Bridge) and something resembling intent.
Carle either had a shot or was looking for Kisel in the box — it was hard to tell.
In the 50th minute Sydney had another good chance. Antonis, who was very quiet in the first half, sent a firm ball through for Carle. It seemed too ambitious but Carle ran hard, got to the ball and Ryan had to make a good save at Carle's feet, hurting himself in the process.
Folks in the stands were getting irate that some of McFlynn's passes weren't finding their mark but one pass fortuitously found Emerton in the left side of the Mariners' box. Ryan came to stop but Emerton shot away from goal in any case.
Bojic made Ryall look silly before sending over a decent cross, punched away by Reddy, setting up Bozanic to shoot high.
Shannon Cole came on to relieve Ryall's misery. But the next trouble came from the other side, where a throw in was met by Ibini and glanced onto the post.
Emerton hit a rubbish pass back and conceded a corner. "Sick," said the guy next to me.
Reddy made a great point-blank stop on Ibini after Beauchamp failed to intercept a cross from the right by substitute Troy Hearfield, who had been sent through by a wonderful ball I can't credit.
In the 66th minute Bridge squeezed a ball through to Kisel, who shot low and firm to Ryan. Then Sydney got into the right of the Mariners' penalty area, where Carle pulled back for Bridge who shot to the right of goal (the sort of thing Cazarine would do).
Sydney were playing with more purpose and Antonis was more involved in moving the ball forward. Cole repeatedly asked for the ball. Getting it once he played a one-two with Carle, who was fouled.
Amini was good sidestepping Antonis and shooting to goal — Reddy down to save.
In the 72nd minute Antonis played a nice ball across the Mariners' goal, just out of reach of Grant.
Hutchinson made a great tackle on Carle as he was heading down the right. Antonis swung a shot over goal (it would have been spectacular ten metres lower).
In the 79th minute Emerton got down the right and hit a pretty good ball for substitute Dimitri Petratos arriving near the left post. The angle was narrow and Petratos was rushing to get there but someone so beloved of the fans should have done better.
Nevertheless, Sydney looked like they could maybe, possibly, even score.
Antonis gave Bridge something to chase but Bridge was offside. Hutchinson again robbed Carle, Emerton gave the ball away again and Beauchamp was thrown forward as Sydney looked for the freak equaliser.
Pascal Bosschaart blocked Adam Kwasnik, supplied by Rose; McFlynn blocked Rose; and Zwaanswijk cleared over Beauchamp.
Grant searched for Beauchamp's head but his cross was too close to Ryan. Bridge shot on a pass from the right and Ryan saved. Sydney won two corners, Rose beating Beauchamp at one and even Reddy's arrival for the second not helping much.
Mariners wound down the time and Sydney lost.
At the press conference Lavicka said Sydney's main problem was mental. "Up here," he said, with fingers on his temples.
Skipper Terry McFlynn said Sydney had a confidence problem but they would take the positives from the second half to their next game against Brisbane Roar.
Arnold said, "Our sloppiness gave them their chances. It wasn't their ability it was our sloppiness.
"Our first 40 minutes was perfect football from us. They didn't have a chance, they couldn't get near us. But in the second half ... we kept them in the game."
He gave credit to "two of the best central defenders in the league" for countering the high balls Sydney had been playing.
He said when the relative budgets of the sides were taken into account it gave him satisfaction how well Mariners were playing.