The experienced coach still hasn't decided on his preferred approach at his new club, with tough choices to be made between a top-heavy attack and loading up the midfield
In the Phoenix's past two matches they have started with a 4-3-3 formation but Merrick has made early substitutions to bolster his midfield as Wellington have struggled in the first halves of their respective draws against Western Sydney and Newcastle.
But Merrick has not given up on his preferred formation just three rounds into his inaugural season with Wellington.
"I like to play with three strikers high whenever possible and when I played with three strikers in the last two games in particular we never really got going in the first half an hour," Merrick told Wellington's website.
"I've had to re-jig the midfield, take off a striker and put on an attacking midfielder and it's worked for us in both those games.
"It's important to have a good quality midfield that can keep possession particularly in the front third.
"If you can keep possession in the front third you can set up scoring opportunities."
Merrick's preferred midfield trio is Manny Muscat and Vince Lia with Carlos Hernandez ahead of them.
That combination does rely on the former two putting in a mountain of work as Hernandez is not renowned for his defensive effort, although Merrick believes time is what the Phoenix need.
"We're still trying to get the midfield right because we haven't played enough games to get the team cohesion we want," the 60-year-old said.
"If we get the midfield right I know we will be a much stronger outfit."
Wellington played 10 games in preseason and although that was very similar to other A-League clubs, the massive changes made by Merrick to the Phoenix's squad (he brought in 11 players, while 16 departed) meant they are still learning to play together.
Next up for Phoenix is Merrick's former club Melbourne Victory at Etihad Stadium on Monday night.
Merrick won two A-League doubles with Victory and will come up against his former captain Kevin Muscat, who has replaced Ange Postecoglou as Melbourne's head coach.