'Blues Traveler' Guy -- CHUGS WHISKEY ... PUKES WHISKEY

He likes coffee ...
And he likes tea ...
But the guy from Blues Traveler can't handle his booze ... and TMZ has footage showing John Popper hurling after trying to chug some whisky on stage.

It all went down last week at a performance at Ponte Vedra Beach, Florida -- when Popper, who had been slamming drinks throughout the show, tried to slam one final cup ... and failed.

We're not here to judge (ok, maybe a little) ... but we've all been there -- and like a true champion, John embraced his failure, and called himself out for the "party foul."

Party on, Blues Traveler guy.

8:34 AM PT -- Popper says there's a damn good reason he heaved -- THERE WAS A BUG IN HIS CUP!!! Gross ...

Here's his tweet: "Man there's some awesomely disturbing footage of me hurling up a bug in my whiskey on TMZ & it seems to be blowing up!Cool! #strangelyproud;)"