Why did characters like Kim Pan-seok from Slam Dunk appear?

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Is it true that they suddenly ended it right before the Slam Dunk Sannoh match?
No matter how much I think about it, I don't understand why they were introduced.
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(If I try to look on the bright side, maybe they were introduced to provide a twist, because if characters like Kim Pan-seok hadn't appeared, readers would have easily predicted that the Sannoh match would be the end.)