The Boston Red Sox murdered the New York Yankees' season on Tuesday ... and danced on their ALDS playoff graves with champagne and beer bottles.

The BoSox narrowly escaped the Yanks' last-ditch effort to tie up the series by winning Game 4 at Yankee Stadium ... and celebrated the 4-3 win by drenching themselves in champagne. And, LOTS of it.

The lit fest kicked off with a motivational speech from Sox manager Alex Cora -- who warned his guys about their next matchup ... the Houston Astros.

But, Mookie Betts and Co. don't seem fazed one bit, 'cause that's when the corks start flyin' (right into a local reporter's face).

The ALCS kicks off on Saturday -- start hydrating now!