Because of his strong physical stature, by 1943 an SS overseer trained him to be a boxer, and had him compete at fights to the death in front of the military personnel.

When the camp in Jaworzno was dissolved because of the advancing Soviet Red Army, thousands of its surviving inmates were sent West on death marches to Germany.

At one point he killed two elderly people who harbored him on their farm because he feared they had discovered he was not a German soldier and would turn him in to authorities.

In January 1947, he won an "Amateur Jewish Heavyweight Championship" organized by the US army in post-war Munich, receiving a trophy by General Lucius Clay.

[6] He won his first twelve fights, but lost against a more experienced boxer, Irish-born Pat O'Connor in Westchester County Center on 5 January 1949.

[7] He had a convincing win on 14 January 1949 in Binghamton, New York, 1:14 into the first of six rounds, when he scored a knockout, with a right cross that broke the jaw of his opponent Billy Kilby.

While looking for work in New York City after the war, Haft experienced an incident of anti-Semitic hostility from a potential employer.

Haft told his life's story to his son Alan Scott in 2003, who edited and published it in 2006, with contributions from historians John Radzilowski and Mike Silver.

The biographical film, titled The Survivor, is directed by Barry Levinson and stars Ben Foster as Haft.