Blueface is nursing fresh wounds suffered in the boxing gym when a guy whipped out a knife and stabbed him during an altercation that started on video.
The rapper, and pretty successful amateur boxer, was training Wednesday morning at a gym in L.A.'s San Fernando Valley when the attacker came into the gym. Security footage posted on Blue's IG shows the trainer, David Kaminsky, trying to get in between the man and Blueface.
It appears there was an argument about something, and Blueface decided he was through talking and hit the guy with several punches -- but then he appears to take something out of his pocket and charge back at Blueface ... the video cuts off before the stabbing.
Kaminsky tells TMZ Hip Hop ... things got heated quickly because the unknown attacker immediately started barking, "I'm gonna kill you" to Blueface as soon as he charged into the gym.
He tells us the guy stabbed Blueface in the leg, and then fled. Witnesses say the guy was in a black Tesla Model S and had a Rottweiler with him.
Blueface's injuries don't seem life-threatening -- paramedics did show up on scene -- but he says he won't be able to compete in a boxing match he had scheduled for October 14.
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