Images from Monday's 2018 World Cup qualifiers
Tim Cahill scored twice, including the extra-time winner, as Australia kept their World Cup hopes alive with a 2-1 victory over Syria in the second leg of the Asian play-off on Tuesday.
The 3-2 aggregate victory sends the Socceroos into an intercontinental play-off in November against the fourth-placed team in North and Central America and Caribbean (CONCACAF) qualifying with a World Cup spot on the line.
Cahill scored Australia's opener with a trademark header in the 13th minute but it was not until 96 minutes later that he kept alive his country's hopes of a fourth successive appearance at the World Cup finals with his 50th international goal.
"I knew I was going to score, I didn't touch the ball much but in the end I delivered," said Cahill, who has played at the last three World Cups.
"That's what I've done my whole life and I'll continue to do it."
The United States, Panama and Honduras, the three nations who could provide the opposition in the intercontinental play-off, play their final qualifiers later on Tuesday.
Syria, who had to play all their "home" qualifiers in Malaysia because of the security situation in their war-torn nation, fought until the very end of the match but ultimately came up short in their bid for a maiden World Cup spot.
The visitors, without five first-choice players through injury or suspension, had made the perfect start in the sixth minute to cancel out Australia's away goal advantage from the 1-1 first leg draw.
Tamer Haj Mohamad dispossessed Mark Milligan in midfield and he fed Omar Al Somah, who outpaced the Australian defence and planted the ball high in the net with his left foot.
Australia lost Brad Smith to injury, bringing dropped midfielder Aaron Mooy on to the pitch, but the Asian champions were back on terms in 13th minute.
Mathew Leckie broke down the right and delivered a pinpoint cross that Cahill was never going to pass up, the 37-year-old forward heading the ball home in his 103rd international.
Australia dominated the remainder of the first half, with Syrian skipper Zaher Medani blocking a Cahill shot after one flowing move and goalkeeper Ibrahim Alma force to save James Troisi and Leckie efforts.
Robbie Kruse carved out the decisive chance in the 109th minute when his perfectly weighted cross to the far post found Cahill, who headed it into the top left-hand corner to the delight of the majority of the 42,136 crowd.
Struggling Italy head for play-offs
Italy battled to a 1-0 win over Albania on Monday with a late Antonio Candreva goal as the struggling Group G runners-up head for the playoffs in a bid to reach next year's World Cup.
Italy squandered several good chances until Candreva, unmarked to the left side of goalkeeper Etrit Berisha, was found with a ball across the area from Leonardo Spinazzola and fired home a powerful shot to give Italy the victory.
“We played a great game, were united in our play and we brought the victory home," said midfielder Lorenzo Insigne.
"Today we sought the victory at all costs and we managed to win. We gave everything and showed that Italy never gives up”.
Struggling Italy face a two-legged playoff against one of the other eight best runners-up from the European qualifying campaign to secure a place at next year's finals in Russia.
Iceland become smallest country to qualify for World Cup
Iceland became the smallest country ever to qualify for the World Cup when they beat Kosovo 2-0 on Monday to book a place at their first finals in Russia next year as winners of Group I.
Gylfi Sigurdsson settled their nerves with a superbly-taken goal five minutes before halftime as Iceland proved that their run to the 2016 European Championship quarter-finals, which included wins over Austria and England, was no fluke.
Sigurdsson also set up the second for Johann Gudmundsson midway through the second half as Iceland completed the campaign by winning their final three games without conceding a goal.
It was a remarkable achievement for a country which has a population of about 350,000. The previous smallest country to have reached the finals was Trinidad & Tobago, in 2006, with 1.3 million people.
Coached by part-time dentist Heimir Hallgrimsson, Iceland finished the group with 22 points from their 10 games.
Until fireworks went off after the final whistle, Monday’s match on a wet Reykjavik night rarely felt like an historic occasion, with the hosts grinding out a routine win against opponents who were more refined technically but lacked punch.
Iceland's starting line-up included four players based in England's second tier, two from the English Premier League, one from Italy's Serie A and one each from the top flights of Denmark, Sweden, Scotland and Russia.
An emphatic 3-0 win in Turkey on Friday had sent Iceland top of the group for the final match, although they struggled to impose themselves against the group's bottom side.
Iceland's seven wins in the group included all five of their home matches where previous World Cup semi-finalists Croatia and Turkey were among the victims.
Shaky Croatia grab World Cup play-off place with 2-0 win over Ukraine
Striker Andrej Kramaric struck two superb second-half goals to grab second spot in Group I for Croatia and a place in the play-offs, as they beat Ukraine 2-0 in their final World Cup qualifier in Kiev on Monday.
Having sacked manager Ante Cacic and replaced him with Zlatko Dalic after a disappointing 1-1 draw with Finland on Friday, the Croatians still looked shaky, winning two corners in the first two minutes but doing little else in the opening half.
Needing a win to grab second place in the group, the home side took control, wasting two great chances around the half-hour mark, with Taras Stepanenko driving a powerful shot outside the post and Yevhen Konoplyanka heading just wide moments later.
The first half finished scoreless and there was little to suggest that Croatia had any chance of breaking the deadlock until Kramaric gave them the lead with their first effort on target.
Luka Modric delivered a pinpoint cross from the right and the striker sent a powerful downward header into the corner of the net in the 62nd minute.
With just four points from their last four games amid some poor performances, the goal did little to settle the Croatian nerves as the Ukrainians pressed forward in an attempt to get back in the game.
Instead, Kramaric scored again in the 70th minute, this time ghosting in at the far post to rifle a deep ball from Ivan Rakitic into the goal to the obvious relief of his team mates.
With Iceland coasting to a 2-0 victory over Kosovo to win the group on 22 points, Croatia took second place on 20 with the Ukrainians finishing in third on 17.
Illarramendi rocket gives Spain narrow win in Israel
Real Sociedad midfielder Asier Illarramendi scored a thumping first international goal to give Spain a 1-0 win away to Israel in Group G on Monday, which rounded off their World Cup qualifying campaign with a ninth victory in 10 games.
Illarramendi appeared on the edge of the area after a Spain corner had been cleared and drove the ball high into the net with the outside of his boot, breaking the deadlock in the 76th minute.
Spain had already sealed their place in Russia as group winners and their only motivation was to keep up their slim chances of being seeded in December's World Cup draw, with the 2010 champions 11th in last month's world rankings.
Israel had long been out of contention for a playoff place, finishing fourth on 12 points, one behind Albania in third. Italy ended their campaign second on 23 points.
Coach Julen Lopetegui made nine changes from the Spain team that eased to a 3-0 win over Albania on Friday, with only Sergio Busquets, who made his 100th appearance for Spain, and captain Sergio Ramos keeping their places.
"We knew this was a difficult game for different reasons but we wanted to win and take another step towards recovering our winning mentality which could help us go on and win the World Cup," Spain goalkeeper Pepe Reina told reporters.
"If you had asked us before the campaign started, we would all have taken the results we got. Italy were the team to beat but every side posed their own difficulties and we've been very consistent, confident in ourselves and we've played in the style we wanted to wherever we've been."
Nervy Serbia through to World Cup after 1-0 win over Georgia
Belgrade was gripped by anxiety before an overwhelming sense of joy and relief greeted Serbia reaching the World Cup with a nerve-jangling 1-0 home win over Georgia, thanks to substitute Aleksandar Prijovic's 74th-minute goal on Monday.
The result, celebrated ecstatically in the cauldron of Red Star's Rajko Mitic stadium, left the Balkan nation top of Group D with 21 points from 10 games, two more than second-placed Ireland who booked a play-off spot with a 1-0 win at Wales.
It is the second time Serbia have reached the finals as an independent nation, having been knocked in the group stages of the 2010 tournament in South Africa and then missing the next three major international soccer championships.
Coach Slavoljub Muslin, a journeyman who had been in charge of a myriad of European clubs before he took over at Serbia for the qualifying campaign, was elated after the success.
"I expected a tough game against Georgia and suspected that the final step would be the most difficult," he told a news conference after the organisers set off spectacular fireworks which rocketed into the night sky over the Serbian capital.
"Georgia were the better side in the first half and I told the players to move up a gear after the break, though we had to keep it tight at the back too."
Prijovic grabbed the winner with a fine finish to delight raucous home fans, who lit several flares to celebrate.
Ireland stun Wales to seal World Cup play-off spot
Ireland ripped up the script by beating Wales 1-0 to secure their place in the playoffs for the World Cup finals on Monday.
A night of raw emotion began with both sides needing three points to secure second spot in Group D behind Serbia and ended with Ireland's visiting fans in delirium thanks to James McClean's goal.
Martin O'Neill's Ireland soaked up the expected Welsh pressure in the Cardiff City Stadium and landed a sucker-punch in the 57th-minute with one of their rare attacks.
It proved a body blow from which Chris Coleman's Wales, who started the night above Ireland in second place and still had eyes on top spot, never recovered as their hopes of reaching a first World Cup finals since 1958 evaporated.
Real Madrid forward and Welsh talisman Gareth Bale, missing the crunch clash through injury, could only watch on helplessly in his seat in the stands as Wales suffered their first defeat in 12 World Cup qualifiers.
Ireland finished the group as runners-up with 19 points, two ahead of Wales who paid the price for too many draws earlier in the campaign. Serbia beat Georgia 1-0 to win the group and qualify for the Russia finals automatically.
"So proud. The players were magnificent playing away from home at a very good Welsh side. To win on their territory was a great result for us," O'Neill said.
"That last half-hour seemed an eternity. We withstood pressure but we knew at some stage we would have to try to win the game and we did. The goal was worthy of winning any game."
Ireland have not qualified for the World Cup since 2002 and have bitter playoff memories, having been knocked out by a controversial France goal in 2010.
They will learn who they must face over two legs when the draw is made on October 17.