Yair Rodriguez might've handed out the greatest knockout in UFC history ... but he didn't escape unscathed ... 'cause dude's whole body is jacked up -- from head to toe.
Literally.
Rodriguez -- fresh off his INSANE last second KO of the "Korean Zombie" -- joined the guys on the "TMZ Sports" TV show (airs nightly on FS1) ... and showed off his battle scars.
"My nose is broken, and both my eyes are purple" ... Rodriguez told us.
But, the worst part?
His freakin' feet are ridiculously swollen .