Brain charity Headway questioned the application of the Premier League’s regulations over head injuries yesterday after Thibaut Courtois played on during Chelsea’s 2-0 win over Arsenal on Sunday.

Chelsea goalkeeper Courtois continued after requiring treatment for a head-knock following a collision with Arsenal forward Alexis Sanchez, before being replaced after further treatment and departing Stamford Bridge for precautionary scans in hospital.

Headway chief executive Peter McCabe said: “The new rules introduced this season were designed to ensure no risks to players’ health were taken.

“They clearly state that ‘If there is any suspicion of the player having sustained a concussion, they must be removed from the field of play, and not allowed to return.’

“This incident calls into question whether these rules are working effectively.

“It is hard to understand how a concussion was not suspected following the sickening clash.”

Courtois was taken off only after fluid appeared to be coming from his ear.

McCabe acknowledged the difficulty of making an assessment from television, but questioned why a “safety-first approach” was not applied.

He added: “Bleeding from one or both ears is one of the symptoms to look out for that requires an immediate visit or return to hospital following a head injury.

“The fact that the bleeding only became apparent 15 minutes after the injury also demonstrates the evolving nature of concussion and highlights why a safety-first approach must be taken with all head injuries.”

Courtois was cleared to play yesterday lunchtime after undergoing precautionary tests following the head injury.

His team said: “Chelsea Football Club can confirm Thibaut Courtois went to hospital during our Premier League game against Arsenal for precautionary tests on a head injury. Those tests came back all clear.

“Thibaut was treated for a minor cut to his ear and was released from hospital last night. He is expected to report for international duty (with Belgium) later this week.”

Chelsea’s first-team squad were afforded a day off by manager Jose Mourinho yesterday as many of the players prepared to play with their national teams after the Blues extended their lead at the top of the Premier League to five points ahead of Manchester City.