Hazel sets herself up in the first few paragraphs of the story as being "unbeatable" in more ways than one. She is the fastest runner, the best person to mind her brother, above all challenges. However, even though she makes herself seem superior, she does admit that this isn't always the case:
The big kids call me Mercury cause I’m the swiftest thing in the neighborhood. Everybody knows that—except two people who know better, my father and me. He can beat me to Amsterdam Avenue with me having a two-fire-hydrant headstart and him running with his hands in his pockets and whistling. But that’s private information.
Knowing that she has her own superior in her father - and seeing that she obviously respects his superiority - foreshadows that Hazel may just find her equal yet.
Another instance occurs when Mr. Pearson comes around to sing up the students for the race.
“Well, Hazel Elizabeth Deborah Parker, going to give someone else a break this year?” I squint at him real hard to see if he is seriously thinking I should lose the race on purpose just to give someone else a break.
In the end, this is what she does, because Hazel realizes that she does not need to be "superior" to be respected.