Entertainer primarily concentrating on person in box (8)

I believe the answer is:

conjuror

'entertainer' is the definition.
(I know that conjuror is a type of music interpreter)

'primarily concentrating on person in box' is the wordplay.
'primarily' suggests taking the first letters.
'person in box' becomes 'juror'.
The initial letter of 'concentrating' is 'c'.
'c'+'on'+'juror'='CONJUROR'

(Other definitions for conjuror that I've seen before include "A sleight-of-hand entertainer" , "Magical entertainer" , "Prestidigitator" , "Man of magic tricks" , "Illusionist, magician" .)

I've seen this clue in The Times.

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