FAllen asleep during a chess game? Absolutely. But more during a poker game. My rating/bankroll tends to go south during these times.
Have you ever fallen asleep during a chess game?

FAllen asleep during a chess game? Absolutely. But more during a poker game. My rating/bankroll tends to go south during these times.
I usually don't play chess as well when I'm asleep. Usually. There are exceptions. Deep sleep is another kind of end game. Or is it a chess engine? I forget.
Actually worse than falling asleep during a game without realizing it is if you accidentally move as the result of a hypnic jerk:
hypnic jerk, hypnagogic jerk, sleep start, or night start, is an involuntary twitch which occurs during hypnagogia, just as a person is beginning to fall asleep, often causing him or her to awaken suddenly for a moment. Physically, hypnic jerks resemble the "jump" experienced by a person when startled, often accompanied by a falling sensation. A higher occurrence is reported in people with irregular sleep schedules.
Causes
One reason for this myoclonic jerk is that when a person starts to sleep the respiration rate starts to fall, the brain sometimes interprets this as if the body is dying, so it sends a pulse in order to wake it up. According to the American Academy of Sleep Medicine there is a wide range of potential causes, including anxiety, caffeine, stress and strenuous activities in the evening.[4]
Do you ever play chess when tired? Easier obviously when online than in person. Have you ever caught yourself dozing during a game? If you play tired or sleep-deprived, you might not even know if you fall asleep.
There's something called [ microsleep ] known to affect millions of sleep-deprived people (many while driving), where you can fall asleep without realizing it and think you've been awake the whole time.