Mediocre and negligent leader getting dumped -- fantastic result (10)

I believe the answer is:

lackluster

'mediocre' is the definition.
(thesaurus)

'negligent leader getting dumped fantastic result' is the wordplay.
'negligent' becomes 'slack' (similar in meaning).
'leader getting dumped' means to remove the first letter (the letter which leads the word is removed).
'fantastic' indicates an anagram.
'slack' with its first letter taken off is 'lack'.
'result' with letters rearranged gives 'luster'.
'lack'+'luster'='LACKLUSTER'

'and' is the link.

I've seen this clue in The Telegraph.

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