Kanna damaged his Achilles tendon in middle school, and while it healed, the injury left him with a lasting problem—he can't jump anymore, partly from the physical damage and partly from the psychological impact of it. This limitation could've ended his volleyball career before it started, but instead of giving up, he focused obsessively on what he could still do: serving. By practicing his serve every single day, he developed into an exceptional server with incredible control over the ball's movement and placement.
His talent showed up when it mattered most. In his final middle school volleyball match, he was brought in as a pinch server, and he came close to pulling off the impossible—nearly dragging his team to victory through sheer serving skill alone. They fell short in the end, but the moment showed what he'd accomplished despite everything working against him.
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