The Netherlands fell to another surprising loss and fellow continental powers Italy and Belgium also struggled in European Championship qualifying on Monday, while Croatia showed off their goal-scoring credentials.
Meanwhile, Wales stayed atop Group B with a 2-1 win over Cyprus and are on course to qualify for their first major championship, with the 2016 tournament in France expanded to 24 teams for the first time.
Swansea midfielder Gylfi Sigurdsson scored both goals as Iceland beat the Netherlands 2-0 to hand coach Guus Hiddink his third loss in four matches since taking over after the World Cup.
The win kept Iceland perfect in three qualifiers and left them level atop Group A with the Czech Republic, who got their third straight win by beating Kazakhstan 4-2 in Almaty.
Italy laboured to a 1-0 win at tiny Malta, where Graziano Pelle scored on his debut. The Azzurri are tied for the Group H lead with Croatia, who routed Azerbaijan 6-0. Belgium trail Wales after a 1-1 draw at Bosnia-Herzegovina.
The top two finishers from the nine groups qualify automatically. The best third-place team also qualifies automatically, and the other eight can qualify through a playoff.