Throughout the 1960s and 1970s Janusz Majewski was one of the top sabre fencers in Poland. Majewski made his first mark on the international stage in 1960 when he won an individual bronze at the World Junior Championships in Leningrad. At the Polish national championships he won silver in 1972, along with bronze in 1967, 1971, and 1975. He had his best record, however, in the team sabre event, becoming a three-time Polish champion (1967, 1971, 1973), in addition to winning 10 silver medals from 1959 to 1972. Majewski represented Poland at the World Fencing Championships, winning a team silver in 1969, followed by a team bronze a year later. These performances earned him a place on the Olympic team for the 1972 München Games, where Poland placed fifth in the team sabre event.