Serbia have all but sealed their place in the World Cup after claiming a 1-0 victory over Republic of Ireland.
Aleksandar Kolarov netted the only goal of the game in the 55th minute, but the sending off of Nikola Maksimovic ensured a nervy finish for the visitors.
However, Ireland failed to take advantage of having the extra man and Martin O'Neill's side now sit in third place in Group D.
Read below to see how the action unfolded in Dublin.
Hello, and welcome to Sports Mole's live coverage of the World Cup qualifier between Republic of Ireland and Serbia.
There's still two World Cup qualifying fixtures to come in October but tonight feels like the night which is going to make or break Republic of Ireland's campaign. After the draw in Georgia, Martin O'Neill's side sit two points adrift of leaders Serbia and unless they can emerge victorious this evening, they are looking at the runners-up spot, and a draw would only make their chances to progressing through to the playoffs even harder. Why? They only sit in eighth out of the ninth runners-up, as it stands. It's a complicated process but make no mistake about it, defeat is not an option for the Green Army.
There's only a small margin of error for both nations tonight. While Ireland can move to the top of the group, they could also find themselves five points adrift of Serbia. A draw would let in Wales, who would move level on points with Ireland and two adrift of Serbia if they can defeat Moldova. We will keep you fully updated as and when the goals go in!
Anyway, without further ado, let's get cracking with the team news, starting with Republic of Ireland.
REPUBLIC OF IRELAND XI: Randolph, Christie, Clark, Duffy, Ward, Walters, Meyler, Hoolahan, Brady, McClean, Long.
O'Neill has decided to make two alterations to the team which started in Georgia, and they both come in midfield. Glenn Whelan and Harry Arter have been dropped to the bench, with David Meyler and Wes Hoolahan the pair to come into the side. Given the heat of Tbilisi, I'm a little bit surprised that more changes haven't been made, but that's the team which O'Neill goes with.
SERBIA XI: Stojkovic, Vukovic, Nikola Maksimovic, Ivanovic, Rukavina, Milivojevic, Matic, Kolarov, Kostic, Mitrovic, Tadic
Serbia coach Slavoljub Muslin has made four changes to the team which began the home clash with Moldova on Saturday, with Vladimir Stojkovic, Jagos Vukovic, Antonio Rukavina and Luka Milivojevic all coming back into the team. Regular watchers of English football will also be familiar with Branislav Ivanovic, Aleksandar Kolarov, Nemanja Matic, Dusan Tadic and Aleksandar Mitrovic.
HEAD TO HEAD! Tonight's match represents the fifth time in which these two teams have faced each other, with three matches ending in a stalemate. Ireland have never defeated Serbia, with the one setback coming in 2014 when Filip Djordijevic netting the winner in a 2-1 triumph in Dublin. The game was a friendly, however, rather than a qualifier.
PREDICTION! It's going to be really difficult for Republic of Ireland to find a balance tonight and while we expect plenty of attacking intent, the uncertainty over their position in the table could go against them. Serbia have plenty of quality in their ranks and we are predicting the visitors to claim a 2-1 win.
The two sides are out on the pitch in Dublin. We have enjoyed some pleasantries but now it is time for the national anthems.
The Aviva Stadium is rocking. Can their side fulfil the expectations of their supporters? It's time to find out...
Serbia get us underway.
CHANCE! From their first attack, Serbia nearly score. The ball finds Matic all on his own on the edge of the area and his shot appears to be at least heading on target until Duffy makes an excellent block.
Like at the weekend, Ireland are doing a lot of chasing in these early stages, especially Long. The forward hasn't really had any meaningful possession. Serbia have settled right into this.
After a foul from McClean, Tadic gets his first chance to whip a free kick into the penalty area, and it takes a fine defensive header to help out Randolph. The corner comes to nothing, but it's all Serbua so far.
Duffy has the ball in the net, but it's offside! The defender thinks he has netted his second header in three days, but he is correctly adjudged to be offside. Much better from the home side, however.
The Irish players are trying to pressurise and rattle their Serbian counterparts at every given opportunity. It's a risky tactic after playing just three days ago, but maybe it is a risk which O'Neill has to take. It has been all Ireland for the past five minutes.
Serbia look dangerous on the break but Ireland are continuing to make all of the running. McClean has just tried his luck from 30 yards but while it was never going to result in a goal, he earned a corner thanks to a deflection.
SHOT! What a strike from Long! It's purely speculative but his 25-yard shot forces a superb one-handed save out of Stojkovic, who tips the ball over the crossbar.
LATEST! We said that we would keep you up-to-date with Wales and that is what we shall do. Chris Coleman's side remain goalless in what is effectively a must-win game.
Aside from that long-range attempt from Long, shots have been few and far between. There have been a few blocks here and there but not many efforts are getting through to the goalkeepers.
SHOT! Kolarov does't need much encouragement to get a shot away from distance but he is a tad ambitious to expect to score from this 40-yard free kick. He is trying to catch Randolph out but he hooks his low strike wide of the post.
Long wins a free kick to the side of the area and Brady is soon standing over the ball. It's a poor delivery, however, with his cross failing to beat the first defender. A waste of an opening.
CHANCE! Serbia go as close as we have come this evening. Tadic does well to get to the byline and after his cutback finds Mitrovic, you expect the Newcastle United forward to score from eight yards. Instead, Randolph scrambles to his left to claw the ball away.
There's an end-to-end feel to this contest now - which isn't ideal for Ireland with less than 10 minutes to go in the first half. They would take 0-0 at the break, but Mitrovic is becoming increasingly involved.
Mitrovic gets his criticism when playing for Newcastle but in the right system, he is a quality striker. On this occasion, he took the ball past two players before winning a corner for his team. Kolarov is found on the edge of the area but his shot is blocked.
SHOT! It's all Serbia now. Rukavina is teed up just inside the Irish penalty area but his first-time strike goes high over the crossbar.
HALF TIME: Republic of Ireland 0-0 Serbia
The half-time whistle goes in Dublin and we remain goalless. There hasn't been that many chances, but both goalkeepers have been required to make a good save to keep their team on level terms. Wales are also drawing with Moldova, so it is as you were as far as Group D is concerned.
Ireland get us back underway.
CHANCE! Within 24 seconds of the restart, Serbia should be ahead. Tadic somehow finds himself in a one-on-one situation at the back but despite creating a shooting opportunity for himself, the Southampton man curls the ball too close to Randolph.
I was about to say that it has been a composed start to the second half from Serbia, but Maksimovic has just gifted a corner to Ireland with a misplaced back-pass. Brady's cross is decent, but a Serbia player heads clear.
BOOKING! The first booking of the match goes to Rukavina, who goes straight through Ward on the touchline.
SHOT! Long is being reduced to pot-shots from distance and on this occasion, it's no more than a scuffed effort into the hands of Stojkovic.
GOAL! Republic of Ireland 0-1 Serbia (Kolarov)
Disaster for Republic of Ireland. A flowing move from Serbia sees Kostic play in Kolarov on the left-hand side of the penalty area and the former Manchester City defender rifles an effort in off the underside of the crossbar. Randolph got a touch, but he had no chance to saving that.
Ireland have had their moments in this match but it is difficult to argue that Serbia don't deserve their goal. They look the more assured on the ball and in defence. It's an uphill battle for O'Neill's men.
SUBSTITUTION! Ireland's first change sees Daryl Murphy introduced for Hoolahan, who had been a doubt for this game.
The frustration is building at the Aviva Stadium. Ireland aren't coming close to getting back into this. They have also put a lot of energy into the opening hour and with just three days since the away fixture in Georgia, it is going to take some effort to find a much-needed equaliser.
RED CARD! Serbia are down to 10 men! Maksimovic tries to intercept a ball which has gone over the top of the defence, but he misses the ball and brings down Murphy. It looks harsh but to the letter of the law, it's a red card.
BOOKING! My word. Mitrovic has just committed the blatant dive you can imagine and Brady has been booked. He's now suspended for the next game!
SUBSTITUTION! A second change for Ireland sees Callu O'Dowda replace Ward. Serbia introduce Stefan Mitrovic for Kostic.
BOOKING! McClean is now booked for a silly challenge on Kolarov and he, too, will miss the Moldova game.
Ireland are raging and so they should be. Murphy is about to get a header on goal from close range, but he is being pulled back by the defender, an infringement which goes unnoticed by the referee.
SUBSTITUTION! It's time for Mitrovic to make way, with Aleksandar Prijovic taking his place. Conor Hourihane has also come on for Ireland, with Meyler making way.
LATEST! Wales have gone ahead in Moldova! Hal Robson-Kanu has got the goal, which could be huge. Ireland need an equaliser.
SUBSTITUTION! A final switch for Serbia sees Nemanja Gudelj come on for Tadic.
SHOT! Despite having a man advantage, Ireland are really struggling to create anything of note. Christie has just dragged a low shot wide of the near post, but the full-back was always going to struggle to beat Stojkovic.
CHANCE! Serbia are down to nine men and Ireland come so close to taking advantage. Murphy finds the ball at his feet after battling for it in the air, but his shot from 16 yards is well blocked by Stojkovic.
There will be five minutes of added-on time.
BOOKING! Stojkovic goes into the book for time-wasting. It's pretty irrelevant because I think Serbia have got this won.
FULL TIME: Republic of Ireland 0-1 Serbia
The full-time whistle goes in Dublin and Serbia have held on to seal an all-important win over Republic of Ireland. Kolarov's goal has sent Serbia five points clear, while Ireland now sit in third after Wales prevailed by a 2-0 scoreline in Moldova.
That will be all from Sports Mole for this match. Thank you for joining us this evening, and we hope to see you again soon. Goodbye for now.
