If any haters are still out there doubting Jake Paul ... boxing champ Lawrence Okolie clearly believes they need to drop that opinion ASAP -- praising the guy as the real deal in the ring following a sparring sesh with the former YouTuber on Wednesday.
Okolie and Paul traded blows at The Kamani Club in Dubai ... getting in work so intensely, they were drenched in sweat.
And, afterward, Okolie said Paul is no joke with the gloves.
"He's better than most boxers," the WBO cruiserweight world champ said, according to boxing reporter Michael Benson.