In 2003 Petersson joined German team
HSG Düsseldorf, followed by
TV Großwallstadt in 2005 and
SG Flensburg-Handewitt in 2007. In 2010 he joined
Füchse Berlin. The same year he was named Icelandic sportsperson of the year. In his first season with the club he won the
2012–13 EHF Cup. After two seasons, where he finished 2nd in the
Bundesliga both times, he won the league in 2016 and 2017 and the
DHB-Pokal in 2018. He also won the
DHB-Supercup in 2016 and 2018. In January 2021 he returned to Flensburg-Handewitt. The following summer he joined
MT Melsungen. On 13 November 2021 he played his 500th game in the Bundesliga. After the 2021-22 season he retired. In July 2023 he returned to handball and signed a one-year contract with
Valur. Here he won the Icelandic cup and the
EHF European Cup. This was the first time an Icelandic club won a European tournament. In November 2023 he joined Qatari team
Al-Arabi on a one-month loan deal. At the age of 44 he won another Icelandic championship title in the 2024-25 season. In July 2025, he announced his retirement.
Seasonal statistics National team Petersson initially played for the
Latvian national team before optaining Icelandic nationality in 2004. In 2005, he played for the
Iceland men's national handball team for the first time. At the
2007 World Championship he finished 8th with Iceland, and was in the top ten goal scorers list. The following year he won silver medals at the
2008 Olympics, losing to France in the final. At the
2010 European Championship he won bronze medals. At the
2011 World Championship he was a part of the all star team, when Iceland finished 6th. He also represented Iceland at the
2012 Olympics where Iceland was knocked out in the quarterfinal by Hungary. He had to withdraw from the
2013 World Championship due to a shoulder injury. He was replaced by
Olafur Stefansson. At the
2015 World Championship he was however back in the team. ==Personal life==