Defender Harry Clarke has joined Ross County on a season-long loan from Arsenal.
The 20-year-old made 35 appearances on loan to Oldham Athletic last season.
County boss Malky Mackay said after Saturday's 0-0 draw with St Johnstone he hoped to sign three players by Tuesday.
"Harry is a player that I have tracked and watched for some time having seen a lot of youth football during my time with the Scottish FA," Mackay said.
"He is a player with talent and ability, but more so he has a tremendous attitude and one that I think is a perfect fit for our club."
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