Guðmundur left Keflavík in July 2002 in order to move to Denmark to play with Brønshøj BK.

He played 15 matches for the Danish club, and spent the 2003 campaign on loan in Iceland with Fram Reykjavik.

After two years away, he rejoined Keflavík in 2004 and spent a further five seasons with the club, making a further 105 first-team appearances and scoring 45 goals.

[5] He subsequently rejoined his former club, Keflavík in July of that year and spent another four seasons with the Úrvalsdeild side, scoring 17 goals in 74 league matches.

[2] By the time he left Keflavík at the end of the 2012 campaign, he had become the club's all-time top appearance maker and goalscorer in top-division football with 81 goals in 255 matches.