An open letter calling for the introduction of temporary concussion substitutions has been signed by former Blackburn Rovers stars Alan Shearer and Chris Sutton.

The forward duo, dubbed SAS during Rovers' golden era, backed the letter written to the International Football Association Board as key figures insisted the current protocols were not working.

Members of IFAB meet in Doha today for its 136th annual general meeting and concussion substitutes will be among a number of topics on the agenda.

In December 2020, IFAB invited competitions to take part in a trial of permanent concussion substitutions, which the Premier League agreed to months later.

While it was viewed as a step forward in the sport’s battle against neurogenerative disease, the option to temporarily replace players while they undergo a head injury assessment is still unavailable.

As in many other facets of the modernising the game, football trails behind other sports such as rugby league, rugby union and cricket in taking real action on concussions.

In both rugby codes players suspected of having a head knock undergo a 10 minute head injury assessment, replaced by a temporary "free" substitute - which becomes permanent if the player fails an assessment, with strict 'return to play' rules and timelines for players who have been concussed.

Key figures from the Professional Footballers’ Association, Jeff Astle Foundation, the Concussion Legacy Foundation and brain injury association Headway have now signed an open letter urging IFAB to go further.

Dawn Astle is daughter of former England international Jeff, who died in 2002 with chronic traumatic encephalopathy (CTE), and co-founder of the Jeff Astle Foundation.

She said: “Put simply, the current rules by IFAB are not working and players are being put at risk.

“This is completely unacceptable. Too often we are seeing players assessed for a complex brain injury on the field of play, with the noise and intensity of a football stadium, and continuing the game only for them to be replaced later on.

"This demonstrates that the current guidelines are failing to prioritise player safety. Change is long overdue.”

PFA chief executive Maheta Molango added: “When determining the laws of the game, player safety and welfare have to be the top priorities.

"Medical teams are being given an impossible task.

“As the representative voice of professional players in England, we have been clear that we want to see the immediate introduction of temporary concussion substitutes.”

Concussion Legacy Foundation UK executive director Dr Adam White said: “We need to do everything we can to support medical professionals to make the best decisions for player safety, that means allowing them the time and space to conduct robust clinical assessments away from the field of play.

“Temporary concussion substitutions are the only way that can happen.”

Rovers' title winning duo Alan Shearer and Chris Sutton, whose dad Mike suffered with dementia before his death in 2020, were among the former professionals to sign the open letter.

The family members of Nobby Stiles, Dave Watson, Peter Bonetti, Frank Worthington and Rod Taylor have also given their support.

Headway chief executive Peter McCabe said: “It is vital we better protect footballers from the dangers of continuing to play after sustaining a concussion – particularly those playing at grass-roots level.

“The introduction of temporary concussion substitutes should have happened years ago and any further delays are simply unacceptable.”

A number of medical professionals, including Dr Willie Stewart, have also signed the letter.

It was Dr Stewart’s FIELD study published in 2019 which found footballers were three and a half times more likely to die from a neurodevelopmental disorder than an age-matched member of the general population.

“Permitting a temporary concussion substitution in football would allow healthcare professionals to conduct more comprehensive assessments and send an important signal to every person in the game to treat head injuries with the necessary care,” the opener letter carrying more than 100 signatures reads.

“We call upon IFAB to immediately implement temporary concussion substitutions in the laws of the game for association football for leagues whereby suitable medical and healthcare coverage and oversight allows concussion assessments to be administered.”