Wilkinson admits the club's rusty 2-0 defeat against Brisbane last week was the Mariners worst performance of the season.

After nearly three weeks without a match the Mariners failed to reproduce the form which had seen them surprise many during the early rounds.

Wilkinson is adamant Mariners fans will witness a more assured performance at both ends of the field against Perth at the Sydney Football Stadium on Saturday night.

It is a crucial match for the Mariners, who have played only two matches in a frustrating month of inactivity.

"The performance against Brisbane wasn't good enough, we all know that," Wilkinson said.

"It was a bad day at the office and we need to improve."

Despite last week's loss the Mariners are still sitting in a good position, while Perth is having a horror run.

Wilkinson expects Perth coach Ian Ferguson, who spent several seasons as Lawrie McKinna's assistant at the Mariners, to have the team fired up for a big performance.

"They'll be a little down on confidence so the first goal is crucial," Wilkinson said.

"If we can pinch an early goal it'll give us a huge lift and make things pretty tough for them."

Wilkinson is again looking forward to the prospect of marking Perth superstar Robbie Fowler.

"I've played him a few times and love the challenge," Wilkinson said.

"He has done so much in the game and still has a lot to give the A-League. Around the 18 yard box he is very dangerous."

Meanwhile, Mariners striker Adam Kwasnik could come off the bench against Perth after missing the Brisbane match with a stomach illness.

The club is also hopeful attacking midfielder Patricio Perez will return from an ongoing hamstring injury.