Calls more about possible competitors (9)

I believe the answer is:

allcomers

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'possible competitors' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'calls more about' is the wordplay.
'about' is an anagram indicator.
'calls'+'more'='callsmore'
'callsmore' is an anagram of 'ALLCOMERS'.

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I've seen this clue in The Daily Express.

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