11:22 AM PT -- 11/10 -- A spokesperson for the Garden Grove Police Dept. tells TMZ Sports cops are investigating the incident.
7:07 AM PT -- The teenage girl who clobbered her opponent during a basketball game this weekend has been banned from playing in future AVAC United games, the organization tells us.
AVAC United is a group made up of teams in Southern California ... and they're the people behind the tourney.
A teenage girl was leveled by a sucker punch in the middle of a basketball game Sunday ... and the violent swing was all captured on video.
TMZ Sports has learned ... the incident went down during a youth basketball game in Garden Grove, Calif. -- after a 15-year-old had bumped into a girl following her jump shot.
In footage of the play, you can see as both girls got back to their feet after the collision -- someone from the crowd appeared to yell, "You better hit her."
That's when the girl in the all-black uniform swung a massive left haymaker that connected with the other girl's throat and face area.
Immediately, the girl crashed to the floor in pain ... and we're told the game was stopped and then eventually canceled over the incident.
The punch victim's mother tells us the girl was injured on the play -- and is suffering from the after-effects so much, she still has yet to return to school.
The girl's mom also tells us she went to cops over it all ... though it's unclear if a criminal investigation is underway.
Originally Published -- 11/9 4:38 PM PT