TMZ Sports has obtained photos of the man who claims he was brutally attacked by ex-middleweight champion Jermain Taylor in a rehab facility earlier this month ... and it's clear, dude got pummeled.

Taylor was placed in the facility after a string of strange and violent behavior, including the shooting of his cousin. He was stripped by the IBF of his middleweight crown several months ago.

As we previously reported, officials in Arkansas issued a warrant for Taylor's arrest after the May 13th incident ... in which the alleged victim was sent to the ICU of a nearby hospital for treatment.

Sources close to the alleged victim tell us ... the man claims he was leaving dinner at the rehab center and was walking back to his sleeping area, when he encountered Taylor.

The man claims he extended his hand to greet Taylor -- but the boxer slapped his hand away and proceeded to beat the crap out of him.

The alleged victim underwent surgery to treat his injuries and is currently on the mend.

Taylor's attorney says the allegations are completely frivolous.

So far, we're told the victim doesn't plan to sue -- but is cooperating with police in the criminal investigation.