Observed borders of early England (4)

I believe the answer is:

eyed

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'observed' is the definition.
(I've seen this in another clue)

'borders of early england' is the wordplay.
'borders of' suggests removing the centre.
'england' becomes 'ed' (I can't explain this - if you can you should believe this answer much more).
'early' with its centre taken out is 'ey'.
'ey'+'ed'='EYED'

Can you help me to learn more?

(Other definitions for eyed that I've seen before include "Watched warily" , "Saw" , "Looked at, warily perhaps" , "Looked at closely" , "Vegetable" .)

I've seen this clue in The Independent.

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