Former England captain Alan Shearer fears he may be at risk of suffering from dementia due to heading footballs during his playing days.
The 47-year-old is the Premier League's record scorer with 260 goals and enjoyed an 18-year career with Southampton, Blackburn and hometown club Newcastle.
Shearer also netted 30 goals in 63 appearances for England but the Match of the Day pundit has revealed he has concerns over his long-term health.
Speaking to the Daily Mirror, he said: "For every goal I scored with a header during a game, I must have practised it 1,000 times in training. That must put me at risk if there is a link."
The Mirror reports that Shearer has had tests to examine how heading the ball has affected his brain.
He added: "The tests were pretty nerve-wracking. I have got a terrible memory. I don't know if that is because I don't listen, but I have got a poor memory.
"When you play football as a professional you expect in later life you are going to have problems with your knees, your ankles, or you back, like I have.
"But never did I think playing football could be linked to having a brain disease. That is why the research has to be done."
Shearer believes more research needs to be carried out and greater support for ex-players with dementia should be on offer.
"Nowhere near enough research has been done," said Shearer. "The authorities have been very reluctant to find out any answers. They have swept it under the carpet, which is not good enough.
"Football must look after old players with dementia and put an end to this sense that once you are done playing, you can be put on the scrapheap.
"It's a tough game, it's a brilliant game, but we have to make sure it's not a killer game."