World Rugby will understandably feel vindicated at having successfully improved the safety of the game’s top players.

“Back in 2011 at that Rugby World Cup, we had a rate where 55 per cent of players who had a concussion stayed on the pitch. Now that figure is less than eight per cent, which means we have a much greater awareness of what concussion is and how to diagnose it,” Dr Éanna Falvey, World Rugby’s chief medical officer, told Telegraph Sport.

“The sanction framework was aimed at trying to standardise the approach when it came to adjudicating and penalising a high tackle, to help referees with consistency and also further deter the activity that leads to head injuries.

“While the sample size is too small to say whether or not we changed behaviour, we certainly saw the officiating behaviour change, and the concussion rate drop. Our analysis and research would indicate that there is an intricate link between high-risk high tackles and head injuries. If we lowered the number of high tackles, we would see a decrease in the concussion rate, so we are very pleased with that.”

The implementation of the High Tackle Sanction Framework led to a spike in yellow and red cards in Japan compared to the previous year, with yellow cards increasing by 74 per cent on average per 1,000 player hours.

Red cards also rose dramatically by 138 per cent. Argentina lock Tomas Lavanini was red carded for a dangerous tackle to the head of England captain Owen Farrell, while other players sent off for dangerous tackles included Ireland’s Bundee Aki, USA’s John Quill - again on Farrell - plus Uruguay’s Facundo Gattas and Canada’s Josh Larsen.