James Jackson Jeffries (April 15, 1875 – March 3, 1953) was a world heavyweight boxing champion.

His greatest assets were his enormous strength and stamina. Using a technique taught to him by his trainer, former welterweight and middleweight champion Tommy Ryan

Tommy Ryan

Tommy Ryan was a famed welterweight and middleweight champion boxer who fought from 1887-1907. Ryan was considered an excellent boxer-puncher, and many consider him one of the all time greatest middleweight champions. His won lost record is 86 wins , 3 losses and 6 draws...

, Jeffries fought out of a crouch with his left arm extended forward. He was able to absorb tremendous punishment while wearing his opponents down.