Match of indescribable quality (5)

I believe the answer is:

equal

'match' is the definition.
(I know that match can be written as equal)

'of indescribable quality' is the wordplay.
'of' says the answer is hidden in the clue.
'EQUAL' can be found hidden inside 'indescribable quality'.

(Other definitions for equal that I've seen before include "Numerically identical" , "Be as good as, match" , "more or less" , "Keep pace with - peer" , "Fifty-fifty" .)

I've seen this clue in The Daily Express.

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