After a spell with German team Borussia Dortmund from January 2001 to January 2003 (winning the Bundesliga title in 2001–02 and reaching the final of the UEFA Cup in the same season), Sørensen returned to Lyn. In 2004 he became their top scorer, with nine goals. In November 2005 he signed a contract with Oslo rivals Vålerenga, something that did not sit well with the supporters of Lyn. He then played two years for Bodø/Glimt in 2008 and 2009 before retiring from professional football.