Double from Iceland's Sigurdsson stuns the Netherlands
The Netherlands suffered a 2-0 defeat away to Iceland, who maintained their perfect start to qualifying thanks to Gylfi Sigurdsson's first-half double.
The Swansea midfielder scored his first goal in the 10th minute from the penalty spot and doubled his tally three minutes before half-time when he fired home a loose ball.
A second defeat in three games leaves the Dutch facing a tough task to progress as they trail Iceland and Czech Republic, who beat Kazakhstan 4-2, by six points.
Wales produced a heroic performance to keep their place at the top of Group B with a 2-1 win over Cyprus in Cardiff.
Midfielder Andy King was given a straight red card two minutes into the second half but Wales - who swept into a two-goal lead inside 23 minutes through David Cotterill and Hal Robson-Kanu before Vincent Laban pulled one back for Cyprus before half-time - held on for their seventh point from nine.
Italy laboured to a 1-0 win in Malta - thanks to Southampton forward Graziano Pelle, who scored on his debut - as both teams finished the game with 10 men. Croatia crushed Azerbaijan 6-0 to join the Italians atop Group H with maximum points.
Elsewhere, Luis Suarez scored his first goals since returning to action following his biting ban with a brace in Uruguay's 3-0 friendly win over Oman.
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