Incidental benefit of bringing fast bowlers back? (4,3)

I believe the answer is:

spin off

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'incidental benefit' is the definition.
(I've seen this before)

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(Other definitions for spin off that I've seen before include "something advantageous?" , "By-product" , "leave the road" , "Extra benefit" , "Incidental benefit" .)

I've seen this clue in The Guardian.

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