Approaching in sportswear reveals flaws (12)

I believe the answer is:

shortcomings

'flaws' is the definition.

'approaching in sportswear' is the wordplay.
'approaching' becomes 'coming' (synonyms).
'in' means one lot of letters goes inside another.
'sportswear' becomes 'shorts'.
'coming' going into 'shorts' is 'SHORTCOMINGS'.

'reveals' acts as a link.

(Another definition for shortcomings that I've seen is " Defects (eg of character)".)

I've seen this clue in The Telegraph.

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