They admit It's like big brother versus little brother as Jordan Thompson takes on Alex de Minaur in a high-stakes all-Australian fourth-round US Open showdown in New York.
Having grown up together in Sydney, de Minaur says he's forever indebted to Thompson for taking him under his wing when the pair first met at Olympic Park more than a decade ago.
De Minaur was a wide-eyed 14-year-old, Thompson five years his senior, the cool kid with wheels and just starting to make his way in the professional ranks.