Despite just four goals in the first three rounds of the season, assistant coach Brett Allison has praised Drew Petrie's performances.

''Drew provides us with a great contest under any long ball that comes in; he rarely gets outmarked,'' he said. ''And if you look at the breakdown of our goals, you'll see we've been able to get a number of goals from those fall-of-the ball situations from Drew's contests,'' Allison told The Age's Matt Murnane.

Providing an example from the game against Geelong, Allison pointed out Petrie's impact went well beyond the stat sheet.

''Harry Taylor wasn't a major influence in coming across for third-up marks and cutting the ball off as it came in, because he had his hands full with Drew,'' he said.

The step up in play from Aaron Edwards (11 goals for the season) and Hamish McIntosh (six goals) has played a big part in North's increased attacking output. The club’s average of almost 139-points a game is ranked second highest in the league.

It hasn't been left to the surrounding forwards to increase their output either with midfielders Brent Harvey, Ryan Bastinac, Leigh Adams, Jack Ziebell, Daniel Wells and Kieran Harper chipping in with 32 goals collectively.

The pressure on Petrie has diminished slightly from last season, a development Allison is pleased with.

''Drew doesn't have to come out and kick four or five goals a week to have that influence any more. And the positive for us is that Drew is going to kick goals this year, so we've got them to come, too.''