Kieran Tierney has been battling a secret shoulder injury which has limited his playing time at Arsenal, according to reports.

The former Celtic star joined the Gunners for £25million in the summer but has been limited to just ten appearances so far.

This was, in part, down to a hip injury he suffered with at Parkhead.

Kieran Tierney explains decision not to turn out for Scotland as Arsenal request he's omitted from squad

He also picked up a thigh problem and was forced to sit on the sidelines and rehab that, too, before he could be chosen to play more regularly.

Now, according to The Athletic, Tierney has also been dealing with a shoulder issue which has added to his list of woes and been one reason interim coach Freddie Ljungberg has not picked him to start yet.

It could also provide the answer as to why Arsenal really requested the defender be pulled from Steve Clarke's Scotland squad earlier this season.