Secure a few nets after hauling them up (6)

I believe the answer is:

fasten

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'secure' is the definition.
(synonyms)

'a few nets after hauling them up' is the wordplay.
'FASTEN' is hidden backwards in amongst the letters.
However, I'm unsure how this is indicated.

Can you help me to learn more?

(Other definitions for fasten that I've seen before include "Tie or join together, fix firmly" , "Attach" , "Fix -- make tight" , "Shut" , "Affix" .)

I've seen this clue in The Irish Times.

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