Presale radiographs play a critical role in informing purchasing decisions for thoroughbred yearlings, yet the relationship between specific radiographic findings and future racing performance has not been well defined. This project undertook the most extensive analysis to date of Australian yearling repository radiographs, examining over 8,600 horses to assess lesion prevalence, interobserver interpretation and links to racing outcomes. The research identified which radiographic lesions are most likely to affect performance, while confirming that others have minimal impact. These findings support more consistent radiograph interpretation, improved buyer confidence and better welfare and longevity outcomes for Thoroughbred horses.