Logan Paul just proved that he was 100% clean for his fight against Dillon Danis ... but his nemesis still isn't convinced -- calling the WWE Superstar a "juicehead."
Remember, the former Bellator fighter constantly accused Paul of using performance-enhancing drugs ahead of their Oct. 14 bout ... but he's adamantly denied the allegations, insisting it was the result of hard work.
Paul backed his talk with his test results from VADA on Thursday ... which clearly state his sample came back "NEGATIVE."
Paul then went on X to troll Danis ... promoting his Prime drink chain in the process.
"I wanna address the steroid allegations before you see any news," Paul said. "I wanna confess ... I have been taking a lot of PRIME energy and putting it in my mouth and swallowing it."
"Haters, you're gonna have to keep trying."
Danis -- who lost his boxing debut to Paul via disqualification -- said the results are bogus ... and still stands by his accusations.
"The testing was a joke, literally," he said. "Piss test after fight, famously easy to beat. Old man in the room wasn’t even paying attention."
"You're a juicehead, and you proved that with the way the testing was done."
If ya thought these two settled their beef in the ring, think again ... but a rematch to solve this issue won't happen -- Logan said he will not fight Danis in MMA, even though he claims he can beat him again.
We covered the drama on the latest episode of TMZ Verified the podcast, available on all podcast platforms.