Lineal championship

In combat sports where champions are decided by a challenge, the lineal championship in a weight class represents an intangible world title initially held by the victor of a bout between top contenders in the division, as commonly interpreted. An alternative, less mainstream perspective suggests that vacancies in divisional championships can only be filled by an undisputed champion. A fighter who defeats the reigning champion in a match within that weight class becomes the next lineal champion. In professional boxing, the informal term for the lineal champion is "the man who beat the man."

A break in the lineage occurs when the current champion either retires or transitions to a different weight class. There is no universally recognized and accepted protocol for how to start each lineage so there is no singular canonical list of lineal champions. It is commonly acknowledged, however, to disregard instances where sanctioning bodies (such as the WBA, WBC, IBF, or WBO) strip a title in the determination of lineal champions.