Career
He also competed at the 1988 Summer Olympics in Seoul, South of Korea, where he was defeated in the quarterfinals. 1984 (as a welterweight)
1st round bye
Defeated Georges Ngangue (Cameroon) 5-0
Defeated Kieran Joyce (Ireland) 4-1
Lost to An Young-Su (South of Korea) 2-3
1988 (as a welterweight)
Defeated Manny Sobral (Canada) 4-1
Defeated Søren Antman (Sweden) 5-0
Defeated Dimus Chisala (Zambia) 5-0
Lost to Kenneth Gould (United States) 0-5
Known as "Joltin" Joni", Nyman turned pro in 1988 and had limited success. Nyman retired in 1998 and returned in 2005 for one bout, retiring with a 14-6-1 record.