Nerve — Dick Francis

Rob Finn was a bit of a misfit: a struggling young jockey in a family of accomplished musicians, a man in love with a beautiful woman who wouldn't have him because they were first cousins, a rider who--just as it looked like he'd break into racing's big time--lost his nerve.

Or did he? The horses had never felt so slow and sluggish beneath him, and he knew there had to be a reason. When he found it he could barely believe it. And when it found him, he could barely breathe....