or more likely (knowing absolutely nothing about his health or injury besides his age), i'd guess he had vision problems because he's 76, the vision problems combined with a rotation on the court caused him to trip and hit his head or break a bone in his torso/pelvis/femur and that hit or break was enough to cause whatever other health problems he had to overwhelm him.

i have a friend who was, for a brief time, the leading authority in the world in knocking over old people and her professional opinion is that most falls (like over 2/3 of them) are caused by vision problems. Keep your eyes checked as you age, and make sure your parents and grandparents (if they're still alive) have current prescriptions because falls can kill you way easier than you think.