New Zealand hooker Andrew Hore has been cited for allegedly striking Wales lock Bradley Davies during Saturday's Test in Cardiff.
Davies was laid out by what appeared to be a punch from behind by Hore just seconds into the All Blacks' 33-10 victory. The Cardiff Blues lock later went to hospital to undergo precautionary checks.
A Six Nations Committee statement said: "Andrew Hore, hooker for New Zealand, has been cited by the IRB's independent Citing Commissioner for allegedly striking an opponent during the match between Wales and New Zealand at the Millennium Stadium on Saturday."
The statement continued: "The relevant incident occurred in the second minute of the match and involved Wales lock forward Bradley Davies.
"The time and date of the hearing, before the IRB's appointed independent judicial officer, have yet to be fixed."
Neither referee Craig Joubert nor his assistants saw the ugly incident, but New Zealand coach Steve Hansen had conceded he expected Hore to be cited.
Wales coach Warren Gatland was left distinctly unimpressed and said: "It does not look the best in the world. It looks like he (Davies) has been caught from behind.
"You do not associate the All Blacks as being a side that resort to cheap shots, and I hope that is not the case and that maybe it was an accident. Bradley was a big loss to us and it took us a bit of time to cope."
New Zealand called Chiefs hooker Hika Elliot into their squad in anticipation of Hore's citing, and with Keven Mealamu struggling with a calf problem ahead of next weekend's meeting with England at Twickenham.