Placed side by side with group opposing (3,7)

I believe the answer is:

set against

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'placed side by side' is the definition.
The definition suggests a verb in its base form which matches the answer.

'with group opposing' is the wordplay.
'with' means one lot of letters go next to another.
'group' becomes 'set' (set is a kind of group).
'opposing' becomes 'against' (I've seen this before).
'set'+'against' is 'SET AGAINST'.

Can you help me to learn more?

(Another definition for set against that I've seen is " Assail; compare, balance".)

I've seen this clue in The Telegraph.

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