World Rugby will not punish Northampton despite ruling that the club's medics wrongfully let George North return to action after a suspected head injury, while Saracens duo Richard Barrington and Brad Barritt will face a disciplinary hearing over a dangerous tackle.
Rugby's global governing body expressed "disappointment" on Northampton's failings, after North fell heavily following a tackle from Adam Thompstone in Aviva Premiership action on 3 December.
World Rugby has insisted, however, that English authorities acted quickly to avoid any repeat of a player returning to action after suffering a suspected concussion.
"Despite the failing by the club to correctly apply World Rugby's head-injury management protocols, World Rugby has recognised that the RFU (Rugby Football Union) and PRL (Premiership Rugby Limited) acted swiftly and appropriately to implement measures with Northampton Saints and other clubs to reduce the probability of future non-compliance," read a World Rugby statement.
North appeared to be knocked unconscious after landing heavily from Leicester wing Thompstone's aerial challenge in the Tigers' 19-11 league win at Welford Road.
The 24-year-old underwent a Head Injury Assessment (HIA) and returned to the fray, but World Rugby has now confirmed North should have been permanently removed instead.
North was later stood down by Northampton, missing three weeks of action as he recovered from his latest head injury issue.
The Wales wing endured an enforced five-month break in November 2014 owing to a string of nasty concussions.
The RFU and Premiership Rugby set up the first Concussion Management Review Group to investigate North's latest head-injury incident, that later highlighted Northampton's shortcomings - but again stopped short of imposing any penalty.
World Rugby has now concluded its own review, claiming "highly constructive" dialogue aimed at avoiding any repeat protocol breach.
"The robust head injury protocols defined within the tournament player welfare standards were not fully adhered to at the match in question," continued the World Rugby statement.
"Prioritisation by the medical staff given to evaluating a potential spinal injury to North was advanced as the principal reason for the non-compliance of head injury protocols.
"Following the incident, the RFU and PRL have communicated with all stakeholders to remind them of their obligations to ensure that immediate and permanent removal is observed in all such cases.
"As part of the review, World Rugby is satisfied that Northampton Saints' medical staff were educated on the permanent removal process.
"World Rugby recognises the actions taken by the RFU and PRL as appropriate in order to re-emphasise the protocols and are encouraged by the renewed efforts.
"While it is impossible to completely remove the risk of error, World Rugby remains disappointed that there was a failure in this case to identify and manage the injury appropriately, in particular considering North's medical history."
Meanwhile, Saracens duo Barrington and Barritt will face a disciplinary hearing on Tuesday for the double tackle that left Exeter lock Geoff Parling concussed in Saturday's Aviva Premiership clash.
Prop Barrington was sent off for a shoulder charge on Parling, while Barritt avoided any punishment on the day despite catching the former England second row in the face with his arm.
Barritt has since been cited for his role in the double challenge that left Parling unable to continue, just 10 minutes into the 13-13 league draw at Allianz Park.
"Richard Barrington and Brad Barritt of Saracens will appear before an RFU Disciplinary panel in London on Tuesday evening," read an RFU statement.
"Barrington was sent off by referee Ian Tempest in the weekend's Aviva Premiership match between Saracens and Exeter Chiefs for making contact with the head of Geoff Parling of Exeter Chiefs.
"He has been charged with dangerous charging, contrary to law 10.4(g), for the incident which occurred in the first half of the match.
"In the same incident, Brad Barritt allegedly tackled Geoff Parling dangerously, making contact with his head and was subsequently cited by the citing commissioner charged with dangerous tackling.
"Both players will appear before a three-person RFU Disciplinary panel chaired by Jeremy Summers on Tuesday, January 10."
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