Either someone was REALLY excited about the Mavericks' big win, or they forgot to clear their phone of some freaky content before Luka Doncic's postgame interview ... 'cause loud sex noises interrupted the whole presser -- and the NBA superstar's reaction was priceless!!
The hilarious moment went down just seconds into the Dallas baller's Q&A following the Mavs' Game 2 victory against the Oklahoma City Thunder on Thursday ... when out of nowhere, moaning rang through the room.
Doncic's eyes got super big and he put his head down to cover his face as a reporter said, "Okay, umm .