Right-winger Patric Kjellberg started his career in 1985 with Falu IF and from 1988-92 played with AIK Solna. He was drafted by the Montréal Canadiens of the NHL in 1988 and joined the club in 1992. But his first stay in North America was not very successful as he played only seven games with the Canadiens during the 1992-93 season, spending most of this season with the Canadiens’ American Hockey League (AHL) affiliate Fredericton Canadiens. In 1993 Kjellberg moved back to Europe and from 1993-95 played with HV71, winning the Swedish title with them in 1995. From 1995-98 Kjellberg played with Djurgårdens IF and was the top goal scorer at the 1998 Swedish Championships. Kjellberg returned to the NHL in the 1998-99 season to play with the Nashville Predators, but was traded to the Anaheim Mighty Ducks during the 2001-02 season. In his NHL career, Kjellberg appeared in 394 games, scored 64 goals and added 96 assists. He also appeared in 10 Stanley Cup playoff games with Anaheim during the 2003 playoffs, going scoreless.
Internationally Kjellberg played at the 1992, 1994 and 1998 Winter Olympics and 1992 and 1998 World Championships. He won an Olympic gold in 1994 and World titles in 1992 and 1998. After finishing his sporting career, Kjellberg worked as a police officer. In 2010 he also became sports manager for Leksands IF.