Well I was just considering one hit wonders guys who won a world title but I see we are throwing in guys who have just had one big win also so here are a few

Primo Carnera--Won a HW title spent most of his career as a 6'5" punching bag

Ingmar Johanssen--Floyd was his biggest win

Ricardo Mayorga--His highlight was Forrest

Gerry Cooney---The night he beat Norton will always be his greatest moment in the ring

Frankie Randall---Chavez was his highlight