السبق والقمار والميسر
Abu Hurayrah (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) said: "Whoever makes a horse take part in a race with two other horses, while not being certain it cannot be beaten, then this is not gambling. On the other hand, whoever makes a horse take part in a race with two other horses, while being certain that it will win, then this is gambling."
عن أبي هريرة عن النبي -صلى الله عليه وسلم- قال: «من أَدْخَلَ فَرَسَاً بين فَرَسَيْنِ -يعني وهو لا يُؤمن أن يسبق- فليس بقمار، ومن أدخل فرساً بين فرسين وقد أَمِنَ أن يسبق فهو قِمَارٌ».
شرح الحديث :
This Hadīth shows that making a horse enter a race, while being uncertain whether this horse will win or not, is fine for it is probable that this or another horse may win. However, if one is certain that his horse will win, then the process falls under the category of forbidden gambling. This Hadīth is weak. However, the majority of jurists stipulated that a third horse should be involved in the race to legitimize the process, without paying anything, so that the contract would be gambling-free.