NORTH Melbourne's Lachlan Hansen believes Aaron Edwards or Josh Smith can fill the void left by key forward Drew Petrie for the first two rounds of 2010.

Petrie will serve a suspension for striking Port Adelaide's Alipate Carlile in round 22, meaning North must reshuffle its attack with another player at centre half-forward.

Edwards (thumb) and Smith (groin) have had interrupted pre-seasons, however Edwards returned to the senior side for last week's NAB Cup loss to Fremantle.

Smith, a dominant forward at VFL level who has had played just seven AFL games, will be considered for Saturday's NAB Challenge match against Hawthorn in North Ballarat.

Though Hansen remains another option - having played in attack as recently as last year - he continues to train under backline coach Shane Watson.

The 21-year-old may yet have a greater role in defence should centre half-back Nathan Grima not overcome a broken finger in time for the season opener.

"We've got a lot of forward options with Josh Smith and Aaron Edwards and Haley (David Hale), so I'm sure one of the forwards will take that (Petrie's position) and I won't have to go down there," Hansen said.

"This year hopefully I'll be sticking to key back and we can let Drewy take the forward line, which he's good at."

Hansen is keen to revisit his form of early last season, where he was among North's better players until he tore a hamstring and spent six weeks out of the senior side.

He then played every match from round 12, but was rotated through a number of roles as Grima retained his place in defence and Scott Thompson flourished at full-back.

"I had a good first five weeks and thought I was going to have a really good year," Hansen said.

"Then I came back into the side and it wasn't really the same. I played a bit forward and didn't play as good footy as I wanted to.

"Hopefully this year I just stay injury-free and have a good solid year in defence."

Subject to match-ups, North is expected to use three tall defenders this season with Michael Firrito likely to have a running role in his return from the midfield.

The intra-club and NAB Cup matches have also suggested Hansen will be given the freedom to break from half-back to provide cover in the centre of the ground.

Hansen said the arrival of coach Brad Scott, a new game plan and new facilities meant there had been a lot to digest over the pre-season, but the players had responded well.

"He (Scott) has given everything to us slowly, not chucking everything at us at once," he said.

"We did some stuff early and we're still learning now. Now the games are coming around, we're just trying to implement it all."

Hansen has played 29 games for North since his selection in the first round (No.3 overall) of the 2006 NAB AFL Draft.