Musannaf Ibn Abi Shayba 28:1059

Abu Usama narrated to us, from Sa’d ibn Sa’id, who said: I heard Ali ibn al-Husayn saying: While the Messenger of Allah (may Allah bless him and grant him peace) was on the expedition of Tabuk, the Ansar said: "Let us race." The Prophet (may Allah bless him and grant him peace) said: "If you wish."