Student or Learner
"Stuttering Spain are level on points with second-placed Northern Ireland in Group F despite Saturday's lacklustre 1-1 draw in Iceland, but they will be wary of Latvia's visit after the Baltic nation beat Nigel Worthington's Irish side 1-0."
Does "Northern Irish" exist and the writer is using "Nigel Worthington's Irish side" instead because it is clear that we are talking about Northern Ireland or people never use it?
Yes, it does exist. I think it's clear which side hemeans as he has already mentioned Northern Ireland.