Not quite sure why there would even be a rock on the running track.
I chose an unlucky and lucky number for the runners in this 4koma. Four (4) is an unlucky number in Japanese. In Japanese it is pronounced "shi" which is the same pronunciation as death. And seven (7) is considered almost globally a lucky number. It's also the most common number rolled with two dice as it is the only possible number with six different combinations (1-6, 2-5, 3-4, 4-3, 5-2, 6-1).