Harry had suddenly gone into a spectacular dive, which drew gasps and cheers from the crowd. Hermione stood up, her crossed fingers in her mouth, as Harry streaked toward the ground like a bullet.
"You're in luck, Weasley, Potter's obviously spotted some money on the ground!" said Malfoy.
Ron snapped. Before Malfoy knew what was happening, Ron was on top of him, wrestling him to the ground. Neville hesitated, then clambered over the back of his seat to help.

Harry Potter and the Philosopher's Stone - Chapter 13 : Nicolas Flamel
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