With her wand trapped inside the Chamber with her old clothing, Hermione had no other weapon than her balled fist ... which she drove powerfully into Neville's face. He was taken so surprised by Hermione's quick attack that he couldn't respond. The truth was, though, that Hermione's punch was so intense, so infused by her roiling magic, that Neville's best blocking spell would have trembled against it. As it was, Neville was smashed against the door of the Ritual Chamber and knocked out cold.