Supervised one at sea securing lines (8)

I believe the answer is:

overseen

'supervised' is the definition.
(I've seen this before)

'one at sea securing lines' is the wordplay.
'at sea' is an anagram indicator.
'securing' is an insertion indicator.
'lines' becomes 'verse' (lines of poetry).
'one' is an anagram of 'oen'.
'oen' enclosing 'verse' is 'OVERSEEN'.

(Another definition for overseen that I've seen is " Supervised".)

I've seen this clue in The Sun and The Times.

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