Sahih Bukhari Volume 9, Book 92, Hadith Number 436.

Narrated By Nafi : ‘Abdullah said, “The Prophet arranged for a horse race, and the prepared horses were given less food for a few days before the race to win the race, and were allowed to run from Al-Hafya to Thaniyat-al-Wada’, and the unprepared horses were allowed to run between Thaniyat-al-Wada’ and the mosque of Bani Zuraiq,” ‘Abdullah was one of those who participated in the race.