Question: Danny Williams is best known for scoring an upset knockout victory against what former professional boxer who won his first 19 professional fights by knockout?

Related documents: [0]  [DOC] Daniel Peter "Danny" Williams (born 13 July 1973) is a British professional boxer. A veteran of the sport since 1995, he held the British heavyweight title twice between 2000 and 2010, and the Commonwealth heavyweight title twice between 1999 and 2006. Williams is best known for scoring an upset knockout victory against Mike Tyson in 2004, which earned him a mandatory WBC heavyweight title opportunity. In the same year, he challenged then-reigning champion Vitali Klitschko, but was stopped in eight rounds. [END] 
[1]  [DOC] Michael Gerard Tyson ( ; born June 30, 1966) is an American former professional boxer who competed from 1985 to 2005. He reigned as the undisputed world heavyweight champion and holds the record as the youngest boxer to win a heavyweight title at 20 years, 4 months and 22 days old. Tyson won his first 19 professional fights by knockout, 12 of them in the first round. He won the WBC title in 1986 after stopping Trevor Berbick in two rounds, and added the WBA and IBF titles after defeating James Smith and Tony Tucker in 1987. This made Tyson the first heavyweight boxer to simultaneously hold the WBA, WBC and IBF titles, and the only heavyweight to successively unify them. [END]  
Answer: Michael Gerard Tyson
Michael Gerard Tyson