LONDON — Former international rugby players are suing rugby's governing bodies after being diagnosed with degenerative brain diseases, and CNN reports that this could be the tip of a very large iceberg, as more players are reporting symptoms of dementia and memory loss.

Among players putting forward a legal case against the game's governing bodies are Steve Thompson, Michael Lipman and Alix Popham.

All three are in their early 40s and have recently been diagnosed with early onset dementia and probable chronic traumatic encephalopathy, or CTE.

CTE is a progressive, degenerative brain disease caused by repeated hits to the head.

Thompson says his memory has deteriorated to the extent that he can't remember playing for England in the 2003 Rugby World Cup final, let alone even being in Australia for the tournament.

Thompson is part of a group of nine former players suing the governing bodies, but a wider group of more than 100 players say they are showing signs of neurological complications and are also interested in pursuing legal action, according to the lawyer co-ordinating the case.