TBD by Editorial
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Marvin Hart

1905-06

The ascension of Hart to the heavyweight throne represented the first break in the chain dating back to John L. Sullivan, as retiring champ James J. Jeffries simply bestowed the lineal title on Hart after Jeffries refereed Hart's 12th-round knockout of Jack Root in 1905.

Still, a case could be made, retroactively, that the lineage remained intact. Hart was propelled into the Root fight, in part, by a 20-round decision win over Jack Johnson, the future heavyweight champ, who would years later overwhelm the unretired Jeffries to reconstitute the lineage. (Hart made just one official defense, giving up the title to Tommy Burns fewer than eight months after it had been awarded to him.)