Crossword Genius

Guard loses head on way in (5)

Ross

I believe the answer is:

entry

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

'guard loses head' is the wordplay.
'guard' becomes 'sentry' (sentry is a kind of guard).
'loses head' means to remove the first letter.
'sentry' with its first letter removed is 'ENTRY'.

'on' acts as a link.

(Other definitions for entry that I've seen before include "List of competitors" , "number competing" , "all runners" , "Lobby" , "One in competition" .)

I've seen this clue in The Mirror.
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