Reference for Bava Kamma 80:14

שור האצטדין אינו חייב מיתה [וכו']: איבעיא להו מהו לגבי מזבח

causes a change [in its status], while the preceding clause [tends to prove that a change in the] control [of the ox]<span class="x" onmousemove="('comment',' I.e., from the hands of the owner to those of the borrower. ');">¹³</span>

Jastrow