Martin O’Neills Republic of Ireland’s 15-game unbeaten run at the Aviva Stadium ended as an experimental team got beaten by Iceland.
Hordur Magnusson’s superb 21st-minute free-kick secured victory as Iceland bossed the first half and then dealt with the Republic’s second-half rally.
Preston’s Daryl Horgan was the pick of the Republic’s four debutants.
New caps John Egan and Conor Hourihane both started with Horgan’s Preston team-mate Andy Boyle also introduced.
After the Republic lacked fluency and urgency in the first half, as Aron Sigurdarson pulled the strings for Iceland, the home side picked up the pace in the second period with Horgan producing a couple of dangerous crosses.
But the home team’s flat first-half display proved their undoing as the Martin O’Neill’s side seemed unable to rouse themselves four days after the devastation of seeing captain Seamus Coleman suffer an horrific double leg fracture.
In Coleman’s absence, Burnley’s Robbie Brady captained the Irish but his normally reliable crossing and set-piece delivery deserved him on a number of occasions.
Republic of Ireland: Westwood (GK), Christie, Egan (Boyle 62), Pearce, Brady, McGeady (O’Dowda 72) Hendrick (Gleeson 62), Hourihane (O’Kane 62), Hayes (Horgan 62), McClean (Long 71), Doyle.
Subs: Doyle (GK), Randolph (GK), Keogh, Ward, Meyler.
Iceland: Kristinsson (GK), Saevarsson (Jonsson 84), Ingason, Sigurdsson (Eyjolfsson, 53), Sigurdarson (Omarsson 64), Bodvarsson, Skulason (Smarason 78), Gunnarsson, Magnusson, Gislason (Skulason 88), Finnbogason (Karlsson 71).
Subs: Halldorsson (GK), Jonsson (GK), Kjartansson, Arnason, Sigurdarson.