Celtic have confirmed Wales international Adam Matthews faces a lengthy lay-off as he prepares to undergo shoulder surgery.
The former Cardiff City full-back, 21, was taken off on a stretcher after 13 minutes of Celtic's 2-0 victory over Motherwell on Saturday.
Having visited a specialist, he is now set to be sidelined for 10-12 weeks.
A statement on Celtic's website revealed Matthews will go under the knife on Wednesday and added: "Everyone at Celtic sends their best wishes to Adam ahead of the surgery and for the weeks ahead."
Matthews has made 91 appearances for the Scottish champions since his move from Cardiff in 2011.
His injury adds to a lengthy list of absences for Wales boss Chris Coleman ahead of their final 2012 FIFA World Cup qualifiers against Macedonia and Belgium.
Nine players have already withdrawn ahead of the two fixtures that Wales must win to avoid finishing bottom of UEFA Group A - which could have damaging repercussions on their seeding in qualifying for UEFA Euro 2016.
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