North Melbourne vice-captain Drew Petrie says the club's senior players, including himself, must take more on-field responsibility in the face of opposition momentum swings.

The Kangaroos blew a 33-point third quarter lead in losing to the Brisbane Lions by 12 points on Saturday night, continuing a nightmare run of fadeouts this season.

Following criticism of the club's leadership in the wake of the defeat, Petrie said the focus should fall on he and his senior teammates, rather than young captain Andrew Swallow or coach Brad Scott.

"I think it's up to your most senior players to pull a side out of those positions, me included," Petrie said on the AFL Exchange podcast.

"So the four most senior players at our footy club are Brent Harvey, myself, Daniel Wells and Michael Firrito.

"Those four, and there's probably another handful of blokes underneath that, it's our responsibility.

"The coach can't be out there – it's up to us."

Petrie was strong in his support of Swallow, saying the midfielder led by example with his hardness at the football, and the players played for him.

Instead he put the heat on himself to perform better.

"After a game of footy, regardless of how you perform individually, you've got to look at how you've helped others in the side perform in those tight situations," the key forward said.

"I'd like to have gotten the side over the line in plenty of those games this year, and I haven't.

"I feel I have the ability to do that."

Petrie said the Kangaroos had to work on locking down when opposition teams got a run on, to prevent two straight goals from becoming five or six.

He also squashed the notion that his team was too attack-oriented, saying defence was a focus before, during and after every game.

But, with finals now appearing unlikely, the 30-year-old encouraged the club's list managers to be aggressive during this year's trade period.

He drew parallels between North Melbourne and Essendon, which recruited Brendon Goddard as a free agent at the end of last year to help bolster its developing midfield.

"From [age] 18 to 23, I reckon we've got as strong a group as any in the AFL," Petrie said.

"So the club's done really well in their recruiting through there.

"The worst part of a trade is that you're going to lose a bloke or a pick – and I'd hate to see anyone go – but I think it's a really good option to go down that path.

"I'm sure there are some good players out there who would complement the side.

"You've only got to look at Goddard going to Essendon – he has just topped them up beautifully.

"I reckon that's the way to go for us."