Premier League clubs are still in the dark on heading limits this season despite top-flight chiefs having had the data from a landmark mouthguard study since the start of June.
On Thursday, a parliamentary report slammed a lack of action from football's stakeholders to fight the sport's dementia crisis.
The mouthguard study, which looked at how heading a ball in different ways impacts the brain, will be used to set heading guidelines in training.
This newspaper understands the data has been with the authorities for several weeks.