George North will not play for Northampton again until he has been assessed by an independent expert in head injuries.
The Welsh wing, who has suffered a series of concussions, was cleared by Saints medics to continue playing during Saturday's Aviva Premiership clash with Leicester despite replays suggesting he had been knocked out following a tackle from Adam Thompstone.
Questions have been raised about whether the player's welfare was best served by his return to action but Northampton released a statement defending their actions, which they insist were fully in compliance with World Rugby's head injury assessment protocols.
The club do, though, admit that the footage available to them at the time was limited and have taken the precautionary steps of withdrawing North from action pending the specialist's verdict.
Northampton said: "As at every Aviva Premiership match, the Saints' medical team has access to video footage to be used to assist the pitchside assessment of injuries. It is important to note this video footage is not always the full range of replay angles available to the TV viewing audience at home.
"The medical team can only base their decisions on the evidence available to them at the time of assessment. World Rugby protocol dictated, given the evidence available to the medical team, the use of a Head Injury Assessment.
"George was fully assessed by the doctor away from the pitch using the established protocols and processes, and passed fit to return to play. As with all such injuries, if evidence suggesting a loss of consciousness had been available to the medical team at the time of assessment, George would not have been allowed to return to the field of play.
"All rugby supporters will no doubt be delighted to learn that George remains well. Nevertheless, Northampton Saints continues to place player welfare as its number one priority, and is referring George to an independent expert as part of the club's ongoing assessment process and George will be stood down from play until this process is complete.
"There is a concussion management and monitoring protocol in place for all Aviva Premiership matches which provides for independent review and the opportunity for more detailed investigation. This is an ongoing process with several stages, and the club looks forward to contributing to this.
"Additionally Northampton Saints is seeking to work with all parties to improve the availability of all footage that may assist team medics with injury management."
Headway - the brain injury association - called for an investigation into why teams do not have full access to replays when assessing head injuries.
Peter McCabe, chief executive of Headway, said: "This situation is very worrying and there needs to be a thorough investigation by Premiership Rugby into this incident.
"The new protocols bought into the game in 2014, clearly state that club doctors should have access to TV replays to help them make the correct decision. Why did doctors entrusted with the welfare of the players not have the same access to TV replays that people watching at home had?
"This incident is extremely worrying as it involves a player who has had lengthy periods out of the game due to concussion. It's also a repeat of a incident which happened while George North was playing for Wales last year."