Sensui should be around Goku at the beginning of DBZ. Nappa rapes.
Yusuke (3 kings saga) would have a better chance against Nappa
Just because people think that Yusuke can fight with Nappa doesn't mean that Sensui can. When they say Yusuke they mean EOS, which is MANY times stronger than Shinobu. Nappa takes this with ease.
Nappa via being the Pattycake Champion. Or by raising his two fingers.
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