Welsh aim wrecked in London borough (8)

I believe the answer is:

lewisham

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'london borough' is the definition.
The definition suggests a singular noun which matches the answer.

'welsh aim wrecked' is the wordplay.
'wrecked' indicates anagramming the letters.
'welsh'+'aim'='welshaim'
'welshaim' is an anagram of 'LEWISHAM'.

'in' is the link.

Can you help me to learn more?

(Other definitions for lewisham that I've seen before include "South London borough" , "South London district; hail mews (anag.)" .)

I've seen this clue in The Times.

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