Possibly yielding to a sincere rancher (10)

I believe the answer is:

estanciero

'rancher' is the definition.
(owner of an estancia - type of cattle ranch)

'possibly yielding to a sincere' is the wordplay.
'possibly yielding' indicates anagramming the letters (the letters could produce or yield the anagram).
'to'+'a'+'sincere'='toasincere'
'toasincere' is an anagram of 'ESTANCIERO'.

(Another definition for estanciero that I've seen is " farmer?".)

I've seen this clue in The Guardian.

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