Joni Nyman won six Finnish titles in three weight categories between 1980 and 1988. He was the Finnish champion in lightweight in 1980, in light-welterweight in 1981-82, and in welterweight in 1984, 1986 and 1988. He also took silvers at the Finnish Championships in 1983 and 1987. The most successful years for Nyman as a boxer were probably 1984-1985. Nyman won bronze at the 1984 Olympics, losing to Korean An Yeong-Su in the semifinal and silver at the 1985 European Championships, losing to Soviet Israel Akopkokhyan in the final. Nyman also won the 1986 Nordic Championships and competed at the 1981 European Championships, 1982 World Championships and 1988 Olympics, losing his first round bout at the Europeans and quarter-final bouts at the Worlds and at the Olympics. After the 1988 Olympics Nyman turned professional and finished his professional boxing career in 2005 with a record of 15 wins (KO 4), 6 losses (KOby 4) and 1 draw. Nyman was selected to the Finnish Boxing Hall of Fame in 2008.