New Zealand's number 8 Kieran Read (centre R) fights for the ball in a maul with South Africa's lock Franco Mostert (centre L) during the Japan 2019 Rugby World Cup Pool B match between New Zealand and South Africa at the International Stadium Yokohama in Yokohama on September 21, 2019. [AFP]

Former top referee Jonathan Kaplan said he had “absolutely no idea” how Australia’s Reece Hodge avoided a red card for his tackle on Fiji’s Peceli Yato as officials came under fire on the opening weekend of the Rugby World Cup.

Hodge prevented Yato from scoring a try in the 26th minute of Australia’s tournament-opening 39-21 win on Saturday by blocking the flanker with a shoulder-led, no-arms challenge to the head that saw the Fijian leave the field with concussion.

It looked a clear case for a sending-off and a penalty try, particularly as World Rugby referees chief Alain Rolland had insisted Monday high tackles would be punished severely, even if that meant a rash of red cards.

Yet no on-field action was taken against Hodge, although the Wallaby wing could still be banned after he was cited yesterday for an act of foul play, with a disciplinary hearing to take place at a date yet to be announced.

Fiji were leading 11-7 at the time of the incident.

“Going into this tournament World Rugby have been very clear about contact with the head and what constitutes a red card under their new High Tackle Sanction framework,” Kaplan wrote in his column for Britain’s Daily Telegraph.

“With that in mind I have absolutely no idea why Reece Hodge was not sent off for his tackle on Fiji’s Peceli Yato.”