What is the prescribed procedure for setting up and managing a race with stakes?

Primary text

The Prophet, peace be upon him, entrusted Ali ibn Abi Talib with setting the terms for a prize race. Ali, in turn, instructed Surraqa ibn Malik concerning the procedure. Surraqa was instructed to line up the horses at the finish line (al-Mithan) and announce if anyone was available to adjust a bridle, carry a boy, or throw down a cloth. If no one responded, he was to say 'Allahu Akbar' three times and release the horses upon the third utterance, leaving the outcome to God's will. Ali himself would stand at the finish line, draw a line, and position two men facing each other at the ends of the line, placing their big toes at the extremities. When the horses passed between them, the official was to declare the leading horse the winner if one horse's ears (or ear/reins) clearly surpassed the other's. If there was doubt, the prize was to be split equally. Furthermore, when matching two races, the finish line should be set at the end of the shorter distance. This entire procedure, detailing the start and finish line setup, is excellent practice and should be followed, as it stems from the command given by the Messenger of God to Ali regarding the entrusted prize money.