Aberdeen's striker crisis has worsened after Ryan Edmondson, the Leeds United player they had brought in on loan until January, suffered an ankle injury in training. 

The Pittodrie club expect the English forward to be out of action for between three and four months. 

The 19-year-old has returned to Leeds to see a specialist who will determine the next steps in his treatment. 

The development is a huge blow to manager Derek McInnes as his top scorer Sam Cosgrove has torn knee cartilage and Curtis Main has been sidelined with a thigh strain. 

Cosgrove was ruled out for between eight to 10 weeks last month.