BRENT Harvey says he began Saturday night's game against Geelong with the green substitute's vest because he has not performed his role for North Melbourne in recent weeks.

The 37-year-old came into the game during the third quarter when Kayne Turner was assessed for concussion, and was activated at three-quarter time after when Turner was subbed out. Harvey finished with 14 touches and four inside 50s.

After the game, Roos coach Brad Scott said the green vest did not serve as a form of punishment for Harvey, but acknowledged the veteran "needed to know if he's not going to listen to my words, he might listen to my actions".

Harvey echoed Scott's post-match sentiments and said he had not been playing his role in the squad. 

"The conversations that I had with Brad during the week was when things aren't going right for our team, I try too hard and do things outside my role," Harvey told Channel Seven on Sunday. 

"It's not a punishment but it sort of half is. 

"We just spoke about playing my role regardless of the scoreboard (and) just going out there and making sure that I fulfil my role for that team." 

Harvey said starting the game as the sub gave him a different perspective into the match. 

"On Wednesday when he (Scott) told me, I embraced that role, I thought I played it pretty well and just wanted to really execute that role as good as I possibly could," he said. 

"I was like another coach on the bench, I was walking up with the guys, telling them what I could see on the ground."

Harvey is two games shy from becoming just the fourth player to reach the 400-game milestone.