Qatadah said “Taking another horse behind one’s horse to urge it on and taking another horse at one’s side are (done) in a horse race.
Sunan Abi Dawud Book 15, Hadith 106
← Previous Hadith The Prophet (ﷺ) said: There must be no shouting or leading another horse at one's side. Yahya added in his tradition: When racing for a wager.

Sunan Abi Dawud Book 15, Hadith 105 Next Hadith → The pommel of the sword of the Messenger of Allah (ﷺ) was of silver.

Sunan Abi Dawud Book 15, Hadith 107