“I know the road ahead will be hard, demanding, painful and ever changing and so ask for understanding and patience.
“I recognise how my brain is deteriorating and how my memory evades me when I don’t want it to and how this causes me distress in situations that are beyond my control.
“I do understand what is happening and that is why I want to address my situation now whilst I am able, because I know there will be days when I don’t understand and I hate the thought of that right now.”
Law, a Ballon d’Or winner in 1964, won 55 caps for Scotland and scored 30 international goals to distinguish himself as one of the country’s greatest ever players.
Law began his career with Huddersfield Town, had two spells at Manchester City and played in Italy for Torino, won the European Cup, two English titles and the FA Cup in his 11 years at Old Trafford.
“Denis Law will always be one of this club’s greatest legends and everybody at Manchester United sends our love and best wishes to him and his family,” the club said.
“We know our fans around the world will also rally behind him. We applaud Denis’s brave words and will continue to offer whatever support we can as he adapts to this challenging condition.”