Watching an eighth grader dunk is remarkable. Now consider 14-year-old Trashaun Willis, who was born without a left arm. The 6″3″ middle schooler from Washington, Iowa can cup the ball with his right, leap out of the gym, and throw down like an elite NBA player.

Take a look:

Willis leads his basketball team in scoring and rebounding, he threw 22 touchdowns as his school’s starting quarterback, and he blazes around the oval on the track team each spring.

According to The Des Moines Register, Willis didn’t start playing competitive basketball until two years ago. Up until then, he battled it out in the backyard with his older brother.

“Eventually, Trashaun started getting used to (meeting that competition, given his physical situation) and taking it on as a challenge,” his stepdad said, “and it made him a better person and a better player…His brother enjoyed trying to get the advantage on him, and I just would never have his brother let up. I would sometimes pull his brother to the side and say, ‘J, don’t be so rough,’ but he didn’t listen to me. He kept going at him. And it made Trashaun who he is today.”

Willis has been able to dunk for a while, but it wasn’t until last week that he threw down in a couple of games, and the above-the-rim action was caught on camera.

“I’m used to getting looked at as like an underdog,” he said. “So it just makes me perform harder and do better and try to do better than everyone else.”

With that attitude, the sky, not the gym roof, is the limit.