Mitrovic joined Newcastle during the summer transfer window, and he has been an instant hit at St. James’ Park – with supporters immediately admiring his passion.
However, McClaren claims that the Serbian has shown a lack of maturity so far, and he wants to see better from the forward in the future.
“Mitro’s come in and he’s been a bit of a target for us," McClaren said to the Chronicle.
“He can get better though, without a shadow of a doubt. I think at the moment he just lacks maturity which I think will come with playing for us and in time.”
Mitrovic initially struggled with disciplinary problems in his early displays in England, but he seems to have cleaned up his act.
Although the 21-year-old still plays with an edge to his game, he is not looking so susceptible to picking up red cards, and that has been an encouraging improvement.
Mitrovic’s partnership with Ayoze Perez has also been very impressive, and Newcastle will be hoping that the pair can continue to flourish as the season progress.
If there is one complaint that could be directed at Mitrovic, it is that he needs to start scoring more regularly, as the powerful front-man has only scored three times in 12 matches.