Professional Finland Hagman grew up playing with
HIFK, appearing with their under-18 and junior teams between 1995 and 1999. He played his first professional games in 1997–98 with HIFK. He appeared in eight games in the
SM-liiga, Finland's top league, and scored his first goal. He split the majority of the 1998–99 season between HIFK's senior and junior teams before he was sent to the
Espoo Blues to complete the season. he remained in Finland. He played with
Kärpät of the
Mestis, the Finnish second division, in 1999–00, and remained with the team for 2000–01 after they gained promotion to the SM-liiga. He led Kärpät with 28 goals that season and finished second on the team in points. Following another 23-point campaign in
2003–04, Hagman signed with
HC Davos of the Swiss
National League A as the
2004–05 season was wiped out by a
labour dispute. He returned to the Panthers to begin the
2005–06 season, but after 30 games, he was traded to the
Dallas Stars in exchange for a seventh-round selection at the
2007 NHL entry draft. Hagman recorded his 100th career NHL point in a 2–1 victory over the
Vancouver Canucks on October 23, 2006. Hagman reached numerous milestones en route to his second 20-goal campaign in
2008–09. He played his 500th NHL game on November 17, 2008, against the
Boston Bruins, scored his 200th point on February 22, 2009, against the
New York Rangers and his 100th goal on March 28, also against Boston. Hagman finished the season with 25 goals and 44 points split between Toronto and Calgary. The Flames then placed the winger on re-entry waivers to allow another team to pick him up for only half his salary. He was subsequently claimed by the
Anaheim Ducks on November 14, 2011, with the Flames remaining responsible to pay the other half of his salary for the duration of his contract.
Europe Following the 2011–12 season, Hagman returned to Europe, signing a deal with
Lokomotiv Yaroslavl of the KHL. In the
2012–13 season for Yaroslavl, he played 49 games in the regular season, scoring 12 goals and providing eight assists. This was then followed by a six-game playoff run in which Hagman went scoreless. In July 2013, the Finnish SM-liiga club
Ässät announced that Hagman had signed for a one-year contract. ==International play==