In episode 9 of the 2011 version of Hnter x Hunter, Kurapika's fight is with the prisoner Majitani. They agree to a battle to the death. Once Majitani realizes he is hopelessly outmatched, he says "I surrender!" (time code 18:41) Kurapika is already in the process of punching him, and knocks him out. The surrender is never acknowledged, and there is a verbal dispute over whether Majitani is dead. The other prisoners claim that Kurapika's match must end before Leorio's can begin. Majitani's surrender is never brought up by either side.
One might argue that in a death battle, surrender is irrelevant. Yet the first match, between Tonpa and Bendot, was also a death battle. Tonpa was allowed to surrender. Presumably this was because when the examiner Lippo explained the rules, he stated, "A winner is declared when the opponent admits defeat" (episode 8, time code 14:17).
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Everything Majitani said and did prior to and during his match with Kurapika was meant to intimidate. Calling for a death match was part of that strategy. He knew he was not really a strong fighter, so I believe his goal was to get Kurapika to surrender.
Why did Majitani's surrender not matter?
One might claim that no one heard it, not even Kurapika. But then dramatically, what was the point in having the surrender in the first place? If it's just going to be there, unexplained and unmentioned, it will just cause some nerd to come to a q&a site and ask about it.
If a tree falls in the forest ...