Paul Arnison has warned TJ Moncur: You are only borrowing the right back shirt.
Arnison’s calf injury means Stuart McCall will be forced into his first change for seven league games when City head to Shrewsbury on Saturday.
Although his injury has been diagnosed as a more minor tear than was initially suspected, Arnison now faces being stuck on the sidelines for at least the next two matches.
Having played second fiddle for much of his time with Carlisle, the summer signing has no intention of missing out on any more action than necessary.
Arnison said: “It’s very frustrating because I’d just started to feel my way and was getting fitter and stronger with every game. But these things happen and TJ has got his chance now. I’m sure he will come in and do a good job.
“It’s up to me, when I’m fit again, to win my shirt back and that’s what I aim to do.
“Every footballer needs competition to keep them going and people fighting for the place. I had it last year with Carlisle and hopefully I can get back quickly to give the manager a tough decision to make.”
Arnison felt a twinge of pain early in the Bournemouth defeat as he chested a cross back to keeper Rhys Evans.
“I knew that something wasn’t right as I landed,” he added. “There was no point in trying to stretch it, so I got off early enough to hopefully not make it any worse.
“I’ve had the same thing before on my other leg and that kept me out for about five or six weeks. But I don’t think this time it’s as bad.
“I couldn’t walk on Saturday but it feels better now and hopefully it will be no more than a couple of weeks.”
Chris Brandon has had an injection in his ankle in a bid to speed up the recovery time from his latest setback.
The midfielder, who faces another fortnight out, is yet to feature at all since signing from Huddersfield after suffering two injuries.
McCall said: “The problem has been identified as a specific point so hopefully getting a jab in there will heal it quicker.
“Chris has been very unfortunate because both incidents were so innocuous and it would be nice to get him back as soon as we can.”