Cardinal's displeasure at court summons originally is diverting (9)

I believe the answer is:

redirects

'is diverting' is the definition.
(to redirect is to divert elsewhere)

'cardinal's displeasure at court summons originally' is the wordplay.
'cardinal' becomes 'red' (cardinal is a shade of red).
'displeasure' becomes 'ire' (I've seen this in another clue).
'at' is a charade indicator (letters next to each other).
'court summons originally' becomes 'cts' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'red'+'ire'+'cts'='REDIRECTS'

I've seen this clue in The Guardian.

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