Lárusson made his debut for Iceland only at the age of 32 in an October 2005 friendly match against Poland, coming on as a substitute for another veteran, 34-year-old Kristján Finnbogason.
Lárusson entered the Icelandic national team at 32 years old in an October 2005 friendly match against Poland, replacing another veteran player, Kristján Finnbogason, who was 34.