North Melbourne forward Lindsay Thomas' suspension was at least in part because of his reputation, says coach Brad Scott.

Thomas was suspended for a high tackle on Western Bulldog Lachie Hunter, in the final quarter of the Kangaroos' 16-point win last Friday night.

"There's no doubt that Lindsay Thomas is paying for sins of the past," Scott said at training on Thursday.

"Did we consider challenging the decision? Yes, we did. We felt it was a tackle gone wrong, correctly paid as a free kick.

"The umpire clearly thought it wasn't reportable. The MRP did, but we're pretty clear of the view that if we challenged it we would have lost, because it was Lindsay Thomas.

"That's what Lindsay's got to deal with."

Thomas' one-week ban means he will miss Sunday afternoon's clash with St Kilda at Etihad Stadium.

Scott said he was aware of how Thomas was is perceived by some in the football community.

"Lindsay's an antagonistic small forward who puts himself in a position where sometimes he gets free kicks (and) sometimes he doesn't," he said.

However, Scott pointed to Thomas' evolution as a person since the coach was appointed at the end of 2009.

"He is an outstanding ambassador for our club," he said.

"If you'd seen a young Lindsay Thomas in 2009, not being able to make eye contact with people he spoke to, to now leading indigenous programs where he presents in front of 80-plus people; he's made a significant transformation.

"But people have got long memories, and Lindsay understands that."

Scott said Robin Nahas would be elevated off the rookie list, as forecast by AFL.com.au earlier in the week. Nahas is a chance to replace Thomas.

"He's one of the potential replacements. We'll elevate him off the rookie list so that we've got that option," Scott said.

"Does that mean he's going to play? We're still not sure yet.

"If it's like-for-like, it's probably Robin. But if we go with a slightly different structure, then there are five or six guys who are putting their hand up."

Key forward Drew Petrie will line-up for his 300th game against the Saints, becoming the fifth Kangaroo to reach that mark.

"Drew's just been the quintessential North Melbourne person. He's a fierce competitor on-field, but he's an absolute gentleman and great family man off the field," Scott said.

Petrie, 33, remains an important part of a forward line that sees the Kangaroos as the second highest-scoring team in the competition.

He is eighth in the competition for percentage of time spent on field, critical in allowing other players to go to the bench in a year when interchange rotations have been limited to 90.