Musannaf Ibn Abi Shayba 37:228

Ja'far ibn 'Awn narrated to us, from Hisham ibn 'Urwah, that Ibn al-Zubayr used to press hard against them until he drove them out from the gates, and he would say: "If I had one peer, I would suffice against him." "We do not bleed from our heels, for our wounds to bleed; but rather, upon our feet, the blood drips."