Players’ union to ring City about level playing field? (8)

I believe the answer is:

equality

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'level playing field?' is the definition.
(I've seen this before)

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(Other definitions for equality that I've seen before include "policy of left-wingers" , "No favouritism being shown" , "correspondence" , "State of being on the same level" , "level playing field" .)

I've seen this clue in The Sunday Times and The Times.

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