Two-time North Melbourne premiership player David King has urged Cameron Zurhaar and fellow young Kangaroos to reciprocate the development of Christian Petracca.

The Demons bull has launched into Brownlow contention in 2020 after working on his aerobic range, which has allowed Petracca to play a majority of his time in the midfield and then rest as a forward.

Zurhaar, a similar frame and role player to a younger Petracca, was headlined as one Kangaroos player King would like to see mimic the shape and capabilities of Petracca in the upcoming off-season.

โ€œNot just Cam Zurhaar. The question for young players is โ€˜how good can I be?โ€™ A lot of young players just wait for 60 or 80 games for the penny to drop. I think they are waiting for nothing,โ€ he explained on Fox Footyโ€™s First Crack.

โ€œThereโ€™s no reason to wait. Look at Christian Petracca and what he has been able to physically do over the last 12 months. Heโ€™s made a decision to consciously change his whole lifestyle and look at the benefits.

โ€œJust in body shape you can see he is a man now, he has dedicated his life to become the full package. I donโ€™t think he wouldโ€™ve expected to have the 2020 he has had.

โ€œTop three in Brownlow betting, clearly going to be Melbourneโ€™s best and fairest winner this season and he is one of the great players in our competition.โ€

King added that Zurhaar could be one pre-season away from taking a massive step in his career.

โ€œIโ€™m watching the Kangaroos game and Iโ€™m thinking โ€˜Cam Zurhaar, what are you waiting for?โ€™ Youโ€™ve played 40-odd games of footy and youโ€™re 22 years of age,โ€ he said.

โ€œIs your body getting to the same shape as a Christian Petracca? And Iโ€™m not going to judge you today because this year has been a difficult year and clearly the hub life has an impact on all those things.

โ€œThis is one of the reasons he can only play in the midfield for 10 minutes because you canโ€™t cover the ground. Now Petracca went through that, Rayner went through that and he is turning the corner.

โ€œI want to judge the first time we see Cam Zurhaar in 2021, when we see a photo in January, I want to see him be the Christian Petracca of 2020.

โ€œEvery club has got them. Iโ€™m just saying Zurhaar because I noticed it.โ€