The inmate who was on the receiving end of a jail house beat down won't have to worry about Aaron Hernandez anytime soon ... 'cause TMZ Sports has learned he's just been released from the slammer.
Law enforcement confirms ... 25-year-old Andrew Booker -- who was in Bristol County Jail on drug and gun charges -- was released from custody Saturday afternoon.
We broke the story ... Booker was in handcuffs when he was attacked by the former New England Patriots star back in February. The two had been having a verbal feud ... and our sources say the feud had lasted for weeks before the fight.
Booker's lawyer claims he suffered cuts, bruises and scrapes in the attack. He also claims Booker is considering taking legal action against the Bristol County Sheriff's Office for allowing the attack to take place.