Although McClaren does not want to see the Serbian getting sent off every match, he is also keen not to take the 21-year-old's aggression out of his game completely.
And, as a result, McClaren has been encouraging the powerful forward to use his physicality in a more positive way during matches.
"He has been playing smart, which is what we have been telling him. Smart and effective," he said.
"He got sent off against Arsenal and could have been against Southampton, but that was a willingness to win and play on the edge.
"That is what you have got to do. We need it from him in every game."
Mitrovic appears to have calmed down in recent weeks, after a very indisciplined start to life at St. James' Park.
Mitrovic has not been booked in any of his last three matches for the Magpies, following his sending off against Arsenal back in August.
His more restrained approach is set to be tested at the weekend though, with a Wear-Tyne derby on the horizon.
Newcastle meet Sunderland on Sunday, and Mitrovic's temperament is sure to be tested in what will be a fiercely contested fixture.