Horny NBA fans are about to get a rude awakening -- those obnoxious World Cup horns are officially vuvuzela non grata at the big Game 7 tonight in Los Angeles.

TMZ spoke with a rep for the STAPLES Center in L.A. -- where the deciding game between L.A. Lakers and the Boston Celtics is scheduled to go down -- and we're told the arena bans ALL noisemakers, "so if you bring a vuvuzela you would not be able to bring it in with you."

Ironically, the ban doesn't seem to include thundersticks -- every foul shot shooter's nightmare -- which arena ushers hand out at halftime.