Medical specialist got hate mail so unfairly (13)

I believe the answer is:

haematologist

'medical specialist' is the definition.
(haematologist is a kind of medical specialist)

'got hate mail so unfairly' is the wordplay.
'unfairly' is an anagram indicator (I've seen this in other clues).
'got'+'hate'+'mail'+'so'='gothatemailso'
'gothatemailso' anagrammed gives 'HAEMATOLOGIST'.

I've seen this clue in The Telegraph.

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