Under current professional boxing rules, a boxer cannot be saved by the bell in any round, including the last round. A fighter must rise after being knocked down, even if the bell sounds to end the round. This is the case in all major sanctioning bodies and the Unified Rules Of Boxing.
Historically, a boxer could sometimes be saved by the bell after being knocked down. The specifics were determined by which of the sanctioning bodies sanctioned the bout, and where it was held. It would often only apply in the last round, and then changed to today’s rule where no saving by the bell occurs in any round.
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