Orlando Bloom hits like a bitch ... so say 3 guys who would know -- MMA stars Tito Ortiz, King Mo and reigning Bellator Lightweight champion Will Brooks.
But the real question -- who would win if there was a rematch between Orlando and Justin??
The guys break down the fighters -- strengths, weaknesses ... well, mostly weaknesses.
Among the highlights:
-- "[Orlando] ... what he threw was so bitch-made, feminine ...it's embarrassing."-- "I think everybody's realizing that [Bieber] might be Miley Cyrus' twin sister."
There's more -- it's hilarious. Watch the clip.