Gambling gains skimmed for life? (7)

I believe the answer is:

innings

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'for life?' is the definition.
(he had a good innings)

I cannot understand how the rest of the clue works.

(Other definitions for innings that I've seen before include "Turns for the batsman" , "Time spent at the crease" , "Time at the crease - a good one's a long life" , "Batsman's spell at wicket" , "knock" .)

I've seen this clue in The Telegraph.

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