Unable to appreciate pitch on defeat sadly

I believe the answer is:

tonedeaf

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'unable to appreciate pitch' is the definition.
I can't judge whether this defines the answer.

'on defeat sadly' is the wordplay.
'sadly' indicates an anagram.
'on'+'defeat'='ondefeat'
'ondefeat' is an anagram of 'TONE-DEAF'.

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I've seen this clue in The Daily Mail.

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