Catch sight of an Eastern agent (4)

I believe the answer is:

espy

'catch sight of' is the definition.
(to espy is to spot or catch sight of)

'an eastern agent' is the wordplay.
'an eastern' becomes 'e'.
'agent' becomes 'spy' (spy is a kind of agent).
'e'+'spy'='ESPY'

(Other definitions for espy that I've seen before include "Spot, notice" , "Pick out at a distance" , "Discern" , "Catch sight of (poetic)" , "Detect" .)

I've seen this clue in The Irish Independent.

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