Arsenal have confirmed that Sead Kolasinac suffered a "significant" injury to his right shoulder in their 3-2 win over Everton on Sunday.
On their official website, the Gunners said he "will undergo further specialist assessments" this week to determine the extent of the problem.
Kolasinac started the match but had to be taken off after just 18 minutes.
This article will be updated to provide more information on this story as it becomes available.
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