In 2001, Samuelsson became the overall champion of the Strongman Super Series. After competing in the IFSA Strongman World Championship in 2005, he returned to compete in the 2006 World's Strongest Man but failed to make it past the qualifying rounds due to a back injury. A year later, Samuelsson reached the 2007 finals, eventually finishing in 5th place. However, after failing to make the finals in the 2008 World's Strongest Man contest, Samuelsson announced his retirement from competition after 14 years competing in the sport. He achieved a 31 podium finish making him one of the all-time most successful strongman competitors. Samuelsson also remains one of only five men to have successfully closed the No. 4 Captains of Crush hand-gripper under official conditions.