The Tarrell Overland Horse Race, also known as the Tarrell Circuit, is the most famous horse race on the frontier. Miradero hosted a race on the circuit in Lucky's first year back in the town. Only men were permitted to race in the Tarrell Circuit. The race had a prize of $500 and a cup trophy. The entry fee was at least $5.
Disguised as a man and without having registered or paid the entry free, Lucky entered the race with Spirit, whom she disguised with colorful war paint. Lucky and Spirit crossed the finish line before Grayson and his horse Xerxes, but Grayson was declared the winner when it was discovered Lucky was not a man, disqualifying her.