ALVARO Morata and substitute Iago Aspas each scored twice as Spain continued to cruise towards the World Cup finals with an 8-0 win over Group G whipping boys Liechtenstein in Vaduz.
Buoyed by Saturday's 3-0 thrashing of closest rivals Italy, the visitors raced into another 3-0 lead inside 16 minutes with goals from Sergio Ramos, Morata and Isco.
David Silva added a fourth before half-time when he was replaced by Iago, who needed just five minutes of the second half to make it 5-0.
Iago turned provider to set up Morata's second in the 54th minute then added a second of his own before Max Goppel's late own goal completed the rout.
Italy effectively sealed at least a play-off place after an underwhelming 1-0 win over Israel, while third-placed Albania were held to a 1-1 draw in Macedonia.
It was hardly the performance required by the Azzurri after their error-strewn defeat to the Spaniards, but Ciro Immobile's 53rd-minute header proved enough to take the points.
Hoping to maintain some pressure on the Italians, Albania went ahead through Odhise Roshi in Strumica, but Aleksandar Trajkovski's late penalty for the home side left them six points adrift and ended their qualifying hopes.
Serbia took another giant stride towards the finals as Aleksandar Kolarov's 55th-minute piledriver secured a 1-0 win over the Republic of Ireland in Dublin.
The Serbians finished the match with 10 men after Nikola Maksimovic's 68th-minute red card while the hosts were furious not to be awarded a late penalty after Daryl Murphy was fouled in the box.
The result gives Serbia a four-point cushion at the top of Group D over Wales, who leapfrogged Martin O'Neill's men into the play-off slot after a 2-0 win in Moldova.
But the Welsh faced a desperate battle to secure the points with Hal Robson-Kanu and Aaron Ramsey scoring twice in the final 10 minutes.
After Robson-Kanu headed the opener Wales keeper Wayne Hennessey produced a brilliant stop to deny Andrei Cojocari before Ramsey sealed it in stoppage time.
Also in Group D, Austria were forced to fight back to grab a 1-1 draw against Georgia in Vienna, Louis Schaub cancelling out an early strike from Valeriane Gvilia.
Two points now separate the top four sides in Group I after leaders Croatia fell to a 1-0 defeat to Turkey in Eskisehir.
Cenk Tosun scored the only goal of the game in the 75th minute to lift the Turks to third place with two games in the group to go.
Iceland moved back into second place, level on points with Croatia, after a priceless 2-0 win over Ukraine in Reykjavik.
New Everton star Gylfi Sigurdsson scored the goals for the hosts either side of half-time.
It marked a welcome return to form for the European Championship quarter-finalists after their shock reversal to struggling Finland on Saturday.
Also in Group I, the Finns continued their improved recent form with a 1-0 win over Kosovo in Shkoder, Teemu Pukki scoring the only goal seven minutes from time.
SYRIA will face a two-legged play-off against Australia to win a place at next year's World Cup finals after a dramatic finish to their Group A game against already-qualified Iran in Tehran.
Omar Al Somah scored three minutes into injury time to grab a 2-2 draw and the point required to pip Uzbekistan to the play-off slot after the Uzbeks were held to a goalless draw by South Korea in Tashkent.
South Korea's point was enough to earn automatic qualification while in Group B a second half Saudi Arabia winner over Japan sent them through alongside their already-qualified opponents.
Syria, who had played all their qualifying games away from home due to the war ravaging their homeland, briefly looked set to book an automatic place after Tamer Haj Mohamed's early goal.
If the Syrians had held out for an improbable victory while South Korea failed to beat Uzbekistan, one of the most improbable World Cup qualifying stories could have been complete.
But two goals from Sardar Azmoun put Iran in control and left the Syrians in danger of missing out completely until Al Somah's late strike which was greeted by delirious scenes in some parts of Damascus.
In Group B, the Saudis and Australia started the night level on 16 points in the race to join Japan in qualifying for Russia, with the Saudis' marginally better goal difference making them favourites.
Fahad Al Muwallad scored his side's crucial goal in the 63rd minute while the Australians toiled to a 2-1 success over Thailand and had to settle for a play-off place.
Tomi Juric put Australia in front after 69 minutes but Pokklaw Anan equalised for Thailand eight minutes from time. Matthew Leckie's winner for Australia four minutes later ultimately proved irrelevant.
In a Group A game with nothing but pride at stake, 2022 hosts Qatar were consigned to bottom place after a 2-1 home defeat by fellow strugglers China.
In Group B, Iraq finished their campaign with a second straight win 1-0 over the United Arab Emirates in Amman.
