Possibly Reg thinks of a red card (4,2,6)

I believe the answer is:

king of hearts

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'red card' is the definition.
'king of hearts' can be an answer for 'card'. I'm not sure about the 'red' bit.

'possibly reg thinks of a' is the wordplay.
'possibly' indicates anagramming the letters.
'reg'+'thinks'+'of'+'a'='regthinksofa'
'regthinksofa' is an anagram of 'KING OF HEARTS'.

Can you help me to learn more?

I've seen this clue in The Irish Independent and The Irish News.

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