Reckless exec, Samuel, offering implausible justification (4,6)

I believe the answer is:

lame excuse

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'implausible justification' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'reckless exec samuel' is the wordplay.
'reckless' indicates an anagram (I've seen this in other clues).
'exec'+'samuel'='execsamuel'
'execsamuel' is an anagram of 'LAME EXCUSE'.

'offering' is the link.

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I've seen this clue in The Everyman puzzle in The Observer.

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