Tottenham have been described as "irresponsible" for failing to substitute Hugo Lloris after the goalkeeper was concussed in a challenge with Romelu Lukaku.
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Lloris was knocked out after colliding with Lukaku during Sunday’s 0-0 draw with Everton at Goodison Park, resulting in a significant stoppage in time.
Spurs manager Andre Villas-Boas defended his decision to let the France international carry on playing rather than replace him with substitute Brad Friedel.
Tottenham tweeted on Monday to confirm that Lloris had received the all-clear after a precautionary scan and reiterate that his condition was fully assessed before he was allowed to rejoin the match on Sunday.
The Club can confirm that Hugo Lloris underwent a precautionary CT scan and was given the all-clear and travelled back to London last night— Tottenham Hotspur (@SpursOfficial) November 4, 2013
However, brain injury charity Headway believe the North London club showed an "irresponsible and cavalier attitude" to Lloris' health by keeping him on the field.
Headway spokesman Luke Griggs told BBC Sport: "When a player -- or any individual -- suffers a blow to the head that is severe enough for them to lose consciousness, it is vital they urgently seek appropriate medical attention.
"A physio or doctor treating a player on the pitch simply cannot accurately gauge the severity of the damage caused to the player's brain in such a setting as there may be delayed presentation of symptoms.
"By continuing to play, the player may have caused greater damage to his brain. He should have been removed from the game immediately and taken to hospital for thorough tests and observation."
Guidelines from both Headway and the National Institute for Health and Care Excellence state that people should not be allowed to play any contact sport for at least three weeks after suffering a concussion.
Griggs added: "Sports science has evolved significantly over the past decade and yet we're still faced with the antiquated concept that a player should be brave and try to continue at all costs. Mr Villas-Boas' comment that his player's determination to play on was proof of his 'great character and personality' is simply wrong and dangerous."