and His Messenger.

• They said: The Prophet ﷺ gave an unqualified ruling that it is permissible to collect prize money (sabaq) for competitions involving camels, horses, and archery, issuing this permission in his capacity as law-giver and without linking it to the presence of a muhallil (a third, risk-free competitor). He said: “No prize money may be taken except in a camel race, a horse race, or archery.” (1)
  If the muhallil were in fact a condition, mentioning it would have been more critical than naming the types of competition—especially if, without the muhallil, the race were unlawful (2) and amounted to gambling according to those who insist on the condition. How could the Messenger of Allah ﷺ grant a sweeping license to take prize money in these events, when in most real cases that license would—on their view—hinge on a muhallil, and accepting the money without him would be forbidden, yet he never clarified this explicitly, implicitly, or by even the slightest hint, nor is there a single report from him or from his Companions during their whole period of wagering that involves a muhallil? (3)
• They also said: In the Musnad of Imam Ahmad (4) it is narrated from Abū Labīd Lamāzah ibn Zabbār: We asked Anas, “Did you place wagers in the time of the Messenger of Allah ﷺ?” He replied, “Yes. The Messenger of Allah ﷺ (5) himself wagered on a horse called Sabḥah; it outstripped the others, and he was overjoyed and pleased.” This narration possesses a good chain of transmission.
  The very fact that this Imam chose to cite it is sufficient proof; the burden of evidence falls on whoever seeks to prohibit it.