Opposes board going by the book (11)

I believe the answer is:

counteracts

'opposes' is the definition.

'board going by the book' is the wordplay.
'board' becomes 'counter'.
'going by' means one lot of letters go next to another.
'the book' becomes 'acts' (I've seen this before**).
'counter'+'acts'='COUNTERACTS'

I've seen this clue in The Telegraph.

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