Displeasing action against the defence (9)

I believe the answer is:

offensive

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'displeasing' is the definition.
(similar in meaning)

I can't explain the remainder of the clue.

(Other definitions for offensive that I've seen before include "Insulting, loathsome" , "Causing resentment or upset" , "nasty in another part of speech" , "Insulting or repulsive" , "Insulting like aggressive attack" .)

I've seen this clue in The Globe and Mail.

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