Incredible news ... UCF quarterback McKenize Milton has been cleared to play football again -- this just roughly 2 years after he almost had to have his leg amputated due to a severe injury.

You'll recall ... the on-field incident was gruesome -- McKenzie dislocated his right knee after taking a vicious shot in a Nov. 2018 game against USF.

Milton's injuries were devastating ... he tore ligaments and an artery, stretched a nerve and had his entire kneecap dislodged.