Substitute fielder? (5)

I believe the answer is:

cover

This clue is a double definition.

'substitute' is the first definition.
(I know that cover is a type of substitute)

'fielder?' is the second definition.
(I've seen this before)

(Other definitions for cover that I've seen before include "the point of cricket" , "Conceal, screen" , "Totally obscure" , "Blanket" , "Lid, travel (distance)" .)

I've seen this clue in The Guardian.

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