The Jets fielded a youngish line-up in their 3-2 win over Western Sydney Wanderers last weekend with the likes of Johnny Koutroumbis, Joey Champness and Angus Thurgate all featuring.

With Newcastle unable to make the finals, Merrick says he will give his younger players more game-time over the final few rounds.

Teenager Jack Simmons is likely to make his A-League debut before the end of this season.

"We'll stick with trying out the youngsters, giving them more game-time," Merrick said.

"Getting them used to the game plan and confident on the ball. At some stage I will probably give Jack Simmons, the 17-year-old, a run. But [the Glory match] is not the type of game for him.

"But given Joey Champness did so well, Evan came on and did well, and Gus Thurgate scored a terrific goal, they'll certainly all be part of the next match.

"For me, when you play against Perth it's the battle for the midfield that's the difference. It was Castro that caught us out last time. So if he's playing we'll need to bear that in mind. You can't man-mark him.

"We need to win the midfield in Perth and that's the hardest thing to do... Tony Popovic has done a great job."

Glory have only lost two games all campaign, but Merrick is confident the Jets will go to Perth full of confidence and intent.

"They're very keen to finish on a high note," he said. "For one reason or another it hasn't worked out for the finals but it should have."

Striker Ronny Vargas remains in doubt to be fit to face Perth on Sunday at nib Stadium.