Musannaf Ibn Abi Shaybah

Hazrat Abu Lubaid (may Allah be pleased with him) narrates that a horse was sent to me while Hazrat Hakam bin Ayyub was the governor of Basra. We went out to see it. We said, "It would be good if we went to Hazrat Anas bin Malik (may Allah be pleased with him)." Then we went to him; he was in the corner of the palace. We said to him, "O Abu Hamza (may Allah be pleased with him)! Did the companions (may Allah be pleased with them) used to compete in horse races during the time of the Prophet (peace and blessings be upon him)?" He said, "Yes, by Allah, the Holy Prophet (peace and blessings be upon him) used to race his horse, whose name was Subhah. Once, it won the race, and then leaves were broken for it."