The 20-year-old dislocated his shoulder during Killie's Clydesdale Bank Premier League win over Hibernian on August 9.

The Scotland Under-21 player suffered a similar injury once before and a visit to a specialist heralded bad news.

"He will be out for six to seven months," Kilmarnock boss Jim Jefferies said.

"The surgeon reckons he will have to perform open surgery as opposed to the keyhole procedure Ryan had before.

"Ryan will do well to return before the end of the season.

"He is young enough to come back but this is extremely unfortunate."