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A wrestler can win by knockout (sometimes referred to as a referee stoppage) if they do not resort to submission holds, but stills pummels their opponent to the point that they are unconscious or are unable to intelligently defend themselves. To check for a knockout in this manner, a referee will wave their hand in front of the wrestler's face; if the wrestler does not react in any way, the referee will award the victory to the other wrestler. If all the active wrestlers in a match are down inside the ring at the same time, the referee will begin a count (usually ten seconds, twenty in Japan). If nobody rises to their feet by the end of the count, the match is ruled a draw. Any participant who stands up in time will end the count for everyone else. In a Last Man Standing match, this form of a knockout is the only way that the match can end, so the referee will count when one or more wrestlers are down, and one wrestler standing up before the 10-count doesn't stop the count for another wrestler who is still down.

How does a referee check for a knockout?
a referee will wave their hand in front of the wrestler's face