Playing in flames is penultimate set of games (4-6)

I believe the answer is:

semi-finals

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'penultimate set of games' is the definition.
The definition suggests a plural noun which matches the answer. I also know that 'games' relates to this answer.

'playing in flames is' is the wordplay.
'playing' indicates anagramming the letters.
'in'+'flames'+'is'='inflamesis'
'inflamesis' is an anagram of 'SEMI-FINALS'.

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I've seen this clue in The Everyman puzzle in The Observer.

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