Bledisloe Cup: Concussion concerns rise again as Sonny Bill Williams wasn't checked after head knock

New Zealand All Black Sonny Bill Williams. Photo / Greg Bowker.

By Iain Payten

SANZAAR are investigating how All Blacks star Sonny Bill Williams suffered an apparent head knock in the opening Bledisloe Cup match and stayed on the field without being checked for concussion.

Footage of Williams suffering an apparent head knock in the 2nd minute has circulated on social media since the game.

The Kiwi centre made a tackle on Wallabies lock Rory Arnold and subsequently had giant New Zealand lock Brodie Rettalick and Aussie rival Adam Coleman fall on him.

Williams appeared very unsteady on his feet when he got up and slowly made his way back to the Kiwi line.

Lack of balance is an indicator to medical staff of potential concussion but SBW was not sent for a HIA.

A SANZAAR spokesman confirmed to News Corp Australia they were looking into the matter after being made aware of footage via social media.

They will discuss Williams' case with the match day doctor, who was appointed by the hosts and the ARU, as per SANZAAR regulations.

-Daily Telegraph