The 28-year-old has been recalled to the Blues side to take on Essendon at the MCG on Saturday, having been sidelined with a calf injury.
Malthouse said the midfielder's performance against the Bombers would not be a factor in any decision.
"We'd be very, very negligent in our duties to suggest that one game is going to be the catalyst for a player going forward or back," Malthouse told reporters on Friday.
The Carlton coach said he would need to sit down with the out-of-contract McLean in the coming weeks.
"It's not that Brock is in a position that he's going to be chopped from the list.
"I want to see where he is.
"There was a hint during the year to me from him that he said he's finding it pretty tough."
Back in May McLean reflected candidly on where his career was positioned, telling AFL.com.au he was a 'year-by-year prospect' and explaining how he'd made changes to make himself a happier footballer.
Malthouse did not want to discuss the future of out-of-contract forward Jarrad Waite.
"He's a free agent, that's the attitude," Malthouse said.
"Most clubs are going to be affected by free agency, one way or the other.
"I don't get too caught up in something that is beyond my control.
"We can paint the picture that this is the place he should play, he may get painted another picture that this is where the money is and this is where you should finish your career."
Skipper Marc Murphy took part in a light training session on Friday morning and is expected to play against Essendon, despite suffering concussion in last week's loss to Port Adelaide.
