Gradually withdrew from stage act and, ignoring the odds, quit (6,3)

'gradually withdrew' is the definition.

'stage act and ignoring the odds quit' is the wordplay.
'stage' becomes 'phase' (phasing is a kind of staging**).
'act' becomes 'do' (I've seen this in other clues).
'and' says to put letters next to each other.
'ignoring the odds' means one should take alternating letters (letters in odd-numbered positions are removed).
The alternating letters of 'quit' are 'ut'.
'phase'+'do'+'ut'='PHASED OUT'

'from' acts as a link.