SANZAAR ruled that Sonny Bill Williams should have undergone a head injury assessment (HIA) assessment during the Bledisloe Cup defeat of Australia last weekend, but cleared New Zealand of misconduct.
Williams took a blow to the head when making a tackle early in the All Blacks' 54-34 win over the Wallabies in Sydney on Saturday.
The 32-year-old appeared to be struggling after sustaining another couple of big impacts, but did not undergo the HIA protocols.
SANZAAR reviewed the incident and concluded that there had been no "deliberate failure" on the part of the world champions in the way they handled the situation.
The Rugby Championship organisers, however, deemed that Williams should have been removed from the field, as footage showed he was suffering from ataxia.
Andy Marinos, SANZAAR's chief executive officer, stated: "This is an unfortunate set of circumstances given the acute focus and attention we are all applying to player safety and in particular the HIA protocols.
"NZ Rugby has been proactive in its management of Sonny Bill Williams and we have full confidence in its processes to manage his return to play - as NZR has illustrated with other players such as Dane Coles and Ben Smith this year already.
"As a consequence, and even though there was no deliberate failure apparent, SANZAAR has taken the opportunity to strongly reinforce World Rugby HIA protocols including video analysis during the game, to all teams, match day medical staff and match officials participating in The Rugby Championship.
"Additionally, New Zealand Rugby has confirmed that Sonny Bill Williams is being managed in line with World Rugby HIA protocols, including HIA 3 and computer neuro-cognitive assessment, and will progress to a graduated return to play if asymptomatic."