McKINNEY, Texas — A male student who witnessed the stabbing of 17-year-old Austin Metcalf testified at the Karmelo Anthony murder trial Saturday that wasn’t aware how badly Metcalf was injured until he lifted his shirt.Subscribe to read this story ad-free Get unlimited access to ad-free articles and exclusive content.“We only knew what happened when he lifted his shirt and saw a big hole,” the student testified.Anthony, 19, was arrested last year and charged in connection with the stabbing of Metcalf — a student from a rival Texas high school — during an altercation at a track meet at a high school in Frisco, Texas. He has pleaded not guilty.The witness said altercation began after Anthony sat uninvited under tent reserved for Metcalf’s school, Memorial High School in Frisco, and refused to leave.The teenager said that several of Metcalf’s tried to get Anthony to leave the tent unsuccessfully. Then, Metcalf took the lead.“Bro just leave ,” he said according to the teen. “We don’t want you here.”The teenager added that Metcalf said he didn’t want to fight and was “calm.” When asked by prosecutors if Anthony was the aggressor, the teenager said: “yes.”“Touch me and see what happens,” Anthony said to Metcalf, according to the teenager. The student then saw Metcalf fall.It was the witness’s first track meet, he said. His identity is not being made public after state district court Judge John Roach Jr. issued an order on Friday barring public identification of any minor witnesses.Racial divisions around the case have propelled it to the national forefront, drawing the attention of both right-wing agitators and civil rights organizations. Anthony is Black; Metcalf was white.Anthony’s attorney is arguing that his client was acting in self-defense. “This case has nothing to do with race,” Texas prosecutor Bill Wirskye said on Thursday during his opening remarks. “This case is not self-defense. Unjustified provoked murder — that’s why we’re here this morning.”Earlier this week, Next Generation Action Network, a civil rights organization that has been advocating in favor of Anthony, denounced the racial makeup of the jurors. Several of the jurors are people of color, but none are Black.Anthony was 17 at the time of the killing. In Texas, 17-year-olds are considered adults. If Anthony is found guilty, he could face five years to life in state prison.He posted a $250,000 bond for his release and has since been under house arrest. Representatives for Anthony have created a crowdfunding page — which has now raised over $600,000 — to help him pay for legal fees and other expenses.Maria Guerrero reported from McKinney, Texas, and Matt Lavietes from New York.