The Mariners were the only team to lock away all three points in Week 1, as four of the five matches ended all square, including United's scoreless draw with Newcastle Jets.

Although the Reds were victorious on their last visit to Gosford back in the final round of the 2008/09 season, United coach Rini Coolen knows overcoming a Mariners outfit coached by former Socceroos boss Graham Arnold and keen to impress in their first home outing of the season, will be a difficult assignment.

"It will be a tough game, that's for sure," Coolen said.

"I saw the game they won against Melbourne Heart, it was a hard and tough game, so they have a lot of confidence now."

Looking ahead to Sunday, Coolen will be hoping the Reds, led by striker Sergio van Dijk, can manufacture more efforts on target after it was an area that let United down against the Jets.

While the Reds are still hampered by a host of players recovering from injury, the return of playmaker Marcos Flores, who was a late withdrawal against Newcastle, is sure to add potency in the attacking third.

Coolen found a number of positives against the Jets despite United failing to find the back of the net, and he maintains that the Reds will chase a win against the Mariners rather than be content with a point on the tough road trip.

"We didn't lose our first game. It wasn't a good game but we didn't lose it," Coolen stated.

"At the start of the competition you have to win games, it doesn't matter how, you have to get points, so we have to go for a result.

"Every game you have to go for three points, even if it's away, so we're going to fight for the three points, you have to start with that."

With Coolen still in the early stages of his coaching tenure in Adelaide and the season just one week old, the Dutchman believes it will take time before every team starts to click on the field, hence the importance of securing points early on in the piece.

"Especially now in the first weeks of the competition, everybody is looking at their system and a way to play better and better every week.," Coolen said.

"So I think it is important at the start of the season to win games, it doesn't matter how, and then you can start getting confidence and playing better football as the weeks go on."

Coolen will be required to reshuffle his defence after the ankle injury to Nigel Boogaard, who was set to face his line up against his former side on Sunday.

United will have its final training session tomorrow morning, with the line up only set to be finalised once the Reds arrive on the Central Coast.

"Training has been really positive so we'll make a decision (on the starting eleven) once we get to Gosford," Coolen said.