Shaq Physically Threatens JaVale McGee

Shaq's playful beef with NBA player JaVale McGee just went NUCLEAR ... with the two men vowing to fight each other ON SIGHT after a series of menacing and threatening tweets.

McGee's been a target of Shaq's 'Shaqtin' A Fool' segment on "Inside The NBA" for years, and apparently had enough when the broadcast devoted a whole segment to his on court screw-ups Thursday night.

JaVale took to Twitter and blasted O'Neal, asking Shaq to kindly get his umm, peanut emojis out of his mouth ... you get the meaning, right?

Shaq wasted no time firing back ... leveling a direct physical threat at the Warriors big man that had ZERO of O'Neal's trademark levity.

"@JaValeMcGee34 don't be acting like u a g I'll smack the s**t out yo bum ass u da one that be looking stupid with your dumb ass #bumass."

Shaq then doubled down, making the threat a promise saying, "we gonna see how tough you are when I see yo ass."

McGee and O'Neal's rift has threatened to get serious before, including a time JaVale called Shaq a "coon" -- a terrible racially charged insult to a black man -- on LIVE TV ... but it's clear that things have now gotten outta hand.