Hafs bin Khaalid (rahimahullah) narrates that an old man who arrived from Mowsil had told him the following:
I once accompanied Hazrat Zubair (radhiyallahu ‘anhu) on one of his journeys. During the course of the journey, while we were in an open, barren land, Hazrat Zubair (radhiyallahu ‘anhu) needed to perform fardh ghusl. He thus said to me, “Conceal me (with a cloth so that I may perform ghusl).” I thus concealed him, and while concealing him, I caught a glimpse of the scars on his upper body from being struck by swords. I thus said to him, “By Allah! I have seen such scars on your body which I have never seen before on anyone else!” Hazrat Zubair (radhiyallahu ‘anhu) asked me, “Did you really see them?” When I replied that I had indeed seen the scars, he said, “By Allah! Know that there is no scar on my body except that I received it in the company of Rasulullah (sallallahu ‘alaihi wasallam) while fighting in the path of Allah Ta‘ala against the kuffaar.
(Tahzeeb-ul-Kamaal 9/321)
‘Urwah (rahimahullah) narrates, “Hazrat Zubair (radhiyallahu ‘anhu) had received three major wounds on his body from being struck by swords. One was on his shoulder, and (it was so big that) I would insert my fingers into it (the hole that was left after the wound healed). Hazrat Zubair (radhiyallahu ‘anhu) received two wounds on the Day of Badr and one on the Day of Yarmuk.”
(Siyar ‘A’laam min Nubalaa 3/33)