Musannaf Ibn Abi Shayba 18:924

Abu Bakr narrated to us, he said: Mughira narrated to us, from Ibrahim, regarding a man who jumped upon another man, so the incisor tooth of the jumper broke, and the one who was jumped upon was wounded. He declared the incisor of the jumper to be void [of compensation], and he held him liable for the wound of the one who was jumped upon.