Mahoney is on-loan at the Blues this season.
Speaking to Birmingham Live about Mahoney, Monk said: “He's been fantastic this season, in terms of coming in here, his attitude and how he's fitted in.
“Everyone can see the ability and potential of him, but he just needs work.
“To be fair to him, in these past five or six games he's taken his opportunity and that's what it's about, no matter what age you are. I've been really pleased with him this season.
“I've had loan players come in before and think they should play every single game and if they don't, they sulk or get a little bit on their high horse and believe they should be playing because they've come from a Premier League club or whatever, but Connor is not like that at all."