The lineal championship in professional boxing, commonly described as "the man who beat the man," is a notional title intended to clarify the modern hodgepodge of sanctioning bodies and alphabet titles. A boxer can only win the lineal championship by defeating the previous lineal champion in the ring. If the lineal champion retires, dies or moves to another division, the vacancy is typically filled by a box-off between two or more top-ranked contenders. Oxnard, Calif., resident and Argentine expat Sergio Martinez ( right ) inherited the lineal title with a unanimous-decision victory over Kelly Pavlik in April 2010. The 37-year-old southpaw made his fifth straight title defense on Sept. 15 with a unanimous-decision victory over WBC beltholder Julio Cesar Chavez Jr.