Result, I suspect, more robust (7)

I believe the answer is:

lustier

'more robust' is the definition.
('lusty' can be a synonym of 'robust')

'result i suspect' is the wordplay.
'suspect' is an anagram indicator (a suspicious or unusual spelling).
'result'+'i'='resulti'
'resulti' anagrammed gives 'LUSTIER'.

(Another definition for lustier that I've seen is " More red-blooded".)

I've seen this clue in The Telegraph.

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