Part of leg that may be off in steak (5,4)

I believe the answer is:

thigh bone

'part of leg' is the definition.
(bone of the leg)

'off in steak' is the wordplay.
'off' becomes 'high' (both can mean rotten).
'in' indicates putting letters inside.
'steak' becomes 't-bone' (T-bone steak is an example).
'high' placed within 'tbone' is 'THIGH-BONE'.

'that may be' acts as a link.

I've seen this clue in The Telegraph.

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