Even for hard-core boxing fans, it is difficult to see how Sean O’Bradaigh emerged as a fearsome light heavyweight. His somewhat posh background, with private schooling and vacations in St. Tropez and Greece, is about as far as can be from those of Mike Tyson or Jake LaMotta.

O’Bradaigh’s father is a private wealth manager from Ireland, and his mother is a Belgian film and theater producer. He grew up in a doorman building a few blocks from the Hudson River, is a strong skier (he actually prefers Aspen to the Alps), and is fluent in French after attending the Lycée Français on the Upper East Side for 15 years. He enjoys brunch with his mother and the occasional Broadway show. He will graduate from New York University in May with a degree in real estate finance. And he can knock you out flat.