Answer
Jan Železný's main rival during his career was Seppo Räty. Železný is a Czech javelin thrower who won gold medals at the 1992, 1996, 2000, and 2004 Summer Olympics. He also set a world record of 98.48 metres in 1996. Räty is a Finnish javelin thrower who won gold medals at the 1991, 1995, and 2003 World Championships. He also set a world record of 91.53 metres in 1991.