Diaper sent was soiled in walker (10)

I believe the answer is:

pedestrian

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'walker' is the definition.
(synonyms)

'diaper sent was soiled' is the wordplay.
'diaper sent' anagrams to 'PEDESTRIAN'.
However, I am not sure how the anagram is indicated.

'in' acts as a link.

Can you help me to learn more?

(Other definitions for pedestrian that I've seen before include "Unexciting" , "Person walking" , "Walker; prosaic" , "Unimaginative" , "nothing much to write home about" .)

I've seen this clue in The Hindu.

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