Antonsson was born in
Karlskrona. He began his career in a local Swedish team called
Sillhövda AIK (1996) and after two years he was transferred to
Swedish champions IFK Göteborg. He played there until 2004, when
Austria Wien bought him for €450,000. In January 2006
Panathinaikos brought him in Athens to play for them on a 2-year contract. In the summer 2007 he moved to the Danish champions
F.C. Copenhagen. Mikael Antonsson started the season 2010–11 impressively with new teammate,
Sölvi Ottesen, which reminded fans of former steady partnership between
Michael Gravgaard and
Brede Hangeland. In the 2–0 win against former club and Greek champions Panathinaikos, Antonsson chosen for the Goal.com Champions League "Team of the Round". In 2011, Antonsson moved to
Bologna in the Italian
Serie A on a free transfer before wrapping up his career in Copenhagen between 2014 and his retirement in 2018. In 2024 Antonsson announced that he will make a comeback by playing for the Swedish tier 4 football club AIK Atlas. == International career ==