Indian river ignored by powerful businessmen who hope to become major players (9)

I believe the answer is:

trialists

'who hope to become major players' is the definition.
(people taking part in trials for a sports team)

'indian river ignored by powerful businessmen' is the wordplay.
'indian river' becomes 'indus'.
'ignored by' is a deletion indicator.
'powerful businessmen' becomes 'industrialists'.
'industrialists' with 'indus' taken away is 'TRIALISTS'.

I've seen this clue in The Guardian.

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