UFC's Khabib Nurmagomedov Gets Medieval In Bloody Cupping Sesh

If the sight of blood makes you sick ... it's probably too late.

Here's UFC star Khabib Nurmagomedov bleeding more than he ever has in a cage ... giving up his back to the medieval practice of wet cupping (aka "Hijama").

FYI, cupping's a form of Eastern medicine that's meant to detoxify blood ... but it's rare you see a celeb messing with Hijama -- which involves making actual incisions.

It's not the most visually appealing process, but Khabib -- a practicing Muslim -- says it's the medicine of the prophet Muhammad (according to the Google translation of his Instagram caption).