World Rugby has requested a full report from the Welsh Rugby Union regarding the apparent head impact sustained by George North in the second half of the clash against England last night.
North left the field for eight minutes during the first half but returned to the fray, missing a tackle on England centre Jonathan Joseph before he crossed for his team's second try.
However, he then appeared to lose consciousness in a 61st-minute incident, but remained on the field of play.
World Rugby, formerly known as the IRB, issued the request today soon after the WRU reported this morning that the winger showed no adverse reaction after suffering a head injury in Wales 21-16 defeat in the Six Nations opener.
World Ruby issued a statement that said: "North, who sustained the impact in the 61st minute of the match remained on the field and, having undertaken an initial review of the broadcast footage, World Rugby is seeking to establish from the WRU whether all concussion management protocols were appropriately followed."
The WRU said in its statement earlier today."He (North) passed head injury protocol tests that were carried out in the medical room in addition to an on pitch assessment.
"He also showed no signs and symptoms when follow up tests were carried out immediately after the game."
Wales prop Samson Lee suffered a concussion and will make a graduated return to training, fly-half Dan Biggar sustained a cut head and full-back Leigh Halfpenny a minor neck injury.
