Chicago Blackhawks goalie Corey Crawford is under investigation by the LAPD after allegedly squirting a heckler in the face with a water bottle during Monday's Game 4 loss to the Kings ... TMZ Sports has learned.
We know ... 27-year-old Kings fan Clark Wong filed a BATTERY report Monday night claiming he was "sprayed" by the hockey player at Staples Center.

TMZ Sports spoke with Wong who says he was sitting behind the Blackhawks bench -- and was heckling Crawford -- when the goalie was pulled from the game toward the end of the 3rd period.

That's when Crawford -- who's in the middle of a 6-year, $36 MILLION contract -- allegedly whipped out a water bottle and blasted him right in the face.