World Rugby has launched a formal review into allegations made by England's Tom Curry over a racial slur in their World Cup semi-final loss to South Africa.

Curry approached referee Ben O'Keeffe during the first half, alleging South African hooker Bongi Mbonambi made the derogatory remark.

The move is poised to disrupt the Springboks build-up to the final against the All Blacks on Sunday morning.

Sportstalk host D'Arcy Waldegrave explains further.

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