Aleksandar Kolarov's second half strike gets Serbia deserved victory against Republic of Ireland 1-0. The win puts Serbia four points clear at the top of the group with two games to play - away at Austria and home to Georgia (6 and 10 October).
Serbia went into the game with an unbeaten record and had the better early chances before took the lead on 55 minutes, when Kolarov hammered a shot in off the bar to silence the home crowd.
Serbian team had to play the last 22 minutes with 10 men after Nikola Maksimovic was sent off.
In the Asian zone qualifiers, Australia will face Syria in a play-off to stay in race for a World Cup, after both teams missed the chance to seal automatic qualification on Tuesday. After defeating Thailand 2-1, Socceroos needed a massive favour from Japan, who last night played Saudi Arabia. But, Japan failed to secure a point in Jeddah, as Saudi substitute Fahad Al-Muwallad scored for 1-0 victory.
Australia now faces two difficult ties against war-torn Syria in October to book a decisive games versus North and Central America's fourth-placed team in November for a spot at the 2018 World Cup.