Now the former Young Socceroos coach is looking overseas for the missing link to shore up his leaky backline before their season is scuttled at launch.

The Mariners have impressed in midfield and attack this season with an overhauled squad that has traded youth for experience and talent.

Danny De Silva has been key as playmaker with Asdrubal lookng dangerous in attack and Wout Brama providing a Dutch of class linking defence and midfield.

But a high pressing line has cost the Mariners repeatedly already this season, with Perth Glory the latest to exploit the exposed weaknesses.

The West Australians turned a Mariners lead into a 2-1 win, hot on the heels of the Gosford side's encouraging 2-2 draw with Western Sydney Wanderers the weekend before.

But the worrying signs were already there for the Mariners in round one when, despite an otherwise strong performance, they were thrashed 5-1 by Newcastle Jets and a ruthless Roy O'Donovan who punished his old side with a hat-trick against them.

But Okon is the first to admit that while his squad has improved on last season, he may still need to bring in a fresh face to help plug the holes at the back.

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"We knew we had to be better," Okon told 442FM podcast. "We had the opportunity to strengthen the squad so we made sure that we did that in the key areas.

"We wanted to bring in some really good experienced players to fill those positions and help the younger players who over the last couple of years have had a lot of football but probably weren't ready for it.

"Having experienced players around, not only in games but every day in training, can only improve the younger players."

But for all the new blood that's been brought in, the Mariners are still looking fragile at the back which is threatening to derail their season.

After just three games, the Mariners have already conceded almost twice as many goals as nearly everyone else in the league  – and a third more even than bottom of the table Brisbane Roar who have lost every game they've played so far.

Now Okon is looking overseas again to fill the gap in defence.

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"We wanted to make sure that we got all of our visa signings right," revealed Okon. "We put most of our resources into that to get those four players.

"There's still room for another visa spot and if there is something affordable and can obviously help the team... we know what sort of position it would be, where we're short.

"Maybe another defender, but we have young Liam Rose and young Jake McGing and they're pretty flexible."

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