[1] He played nineteen seasons in the Úrvalsdeild karla, winning the Icelandic championship six times with Keflavík.
[3] Despite having joined AUM, Guðjón played with Keflavík during the 1991 Cup finals and the 1991 Úrvalsdeild playoffs.
[6] After the 2002–2003 season, he became co-coach of Keflavík with Falur Harðarson and announced he would not continue playing with the team.
[8] After starting the 2005–2006 season with Léttir in the 2. deild karla, Guðjón returned to Keflavík in November 2005 as an assistant coach and player.
[11] Guðjón coached Keflavík during the 2003–2004 season along with Falur Harðarson and together they guided the team to the 2004 national championship.