Imagine being a high school QB or running back and seeing a seven-foot, 440-pound defensive lineman coming after you at full speed. Well, that’s exactly what the unfortunate opponents of Martin Luther King High School in Riverside, California, will be seeing when they square off against the school’s varsity football team, where John Krahn plays on the defensive line.

No matter who lines up against him, Krahn towers over the wide-eyed competition. Truth is, the high school senior would tower over most collegiate and even pro football players. He may be the biggest athlete to have ever played the game. According to Stephen Spiewak of MaxPreps, Krahn is believed to be the tallest high school player in the country and is taller than any player in NFL history.

No surprise, the big man has always been well above average in size for his age. In sixth grade he was already a six-footer, and by his sophomore year in high school he jumped to 6’8″, 330. Fortunately for opposing teams, he’ll be graduating this year and taking his huge frame to the next level. He’ll then be someone else’s very large headache.

Check out the video to see just how much Krahn dwarfs his opponents.