Top Valencia manager dealt with most serious part of complaint (8)

I believe the answer is:

gravamen

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'most serious part of complaint' is the definition.
The definition suggests a singular noun which matches the answer.

'top valencia manager dealt' is the wordplay.
'top' indicates taking the first letters.
'dealt' indicates an anagram.
The initial letter of 'valencia' is 'v'.
'v'+'manager'='vmanager'
'vmanager' anagrammed gives 'GRAVAMEN'.

'with' acts as a link.

Can you help me to learn more?

(Other definitions for gravamen that I've seen before include "Principal ground of complaint" , "Main point (of accusation)" , "Substance of charge" , "serious complaint?" , "Essential part of accusation about grave man" .)

I've seen this clue in The Hindu.

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