Cape Town - Ireland have sent an SOS to South African-born Ulster hooker Rob Herring ahead of their Rugby World Cup quarter-final showdown against New Zealand in Tokyo on Saturday.

Kick-off is at 12:15 SA time.

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Herring, 29, educated at SACS in Cape Town, will replace the injured Sean Cronin, the BBC reported on Wednesday.

Cronin has been ruled out of the tournament after suffering a neck injury in training.

Herring has earned eight caps for Ireland since his debut in 2014 and narrowly missed the cut when coach Joe Schmidt named his 31-man squad for the tournament in Japan.

Ireland captain Rory Best will start against defending champions New Zealand in Tokyo with Niall Scannell now vying with Herring for a place on the bench.