QPR chairman Tony Fernandes brought in a host of big names in the final days of the summer transfer window.
The likes of Joey Barton and Shaun Wright-Phillips moved to Loftus Road after Fernandes' takeover of the West London club.
And the Malaysian businessman has promised to splash the cash again next month when the transfer window opens.
The extra competition for places could put pressure on Mackie to nail down a starting spot.
Mackie told The Sun: "As long as I'm playing I'm happy, like any player. If I'm not playing then I won't be happy.
"I'm playing football at the moment and that's all I want to do – have minutes on the pitch.
"If that doesn't happen after January, I'll address it then. But there's no need to think about it now because the manager's playing me.
"Competition is only a good thing for me – it improves me.
"I've got to raise my game and playing with other players in training will do that.
"I'm not scared of competition."