Sailors in similar European race (11)

I believe the answer is:

sammarinese

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'european race' is the definition.
The definition suggests a singular noun which matches the answer.

'sailors in similar' is the wordplay.
'sailors' becomes 'marines' (I can't justify this - if you can you should believe this answer much more).
'in' indicates putting letters inside.
'similar' becomes 'same' (associated in meaning).
'marines' put into 'same' is 'SAMMARINESE'.

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I've seen this clue in The Times.

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