Republic of Ireland's hopes of qualifying for the World Cup were dealt a huge blow on Tuesday after a 1-0 defeat to 10-man Serbia at the Aviva Stadium.
Martin O'Neill's side started the evening with the chance of going top of Group D with a victory but former Manchester City full-back Aleksandar Kolarov (55) scored the only goal of the game as Serbia, who finished the game with 10 men after Nikola Maksimovic's 68th-minute red card, secured a top-two finish.
Serbia moved four points clear at the summit but for the hosts, who drop down to third in the group, defeat leaves them with a mountain to climb to reach next summer's tournament in Russia, especially after Wales' 2-0 victory in Moldova.
O'Neill asked for a response from his side following their disappointing draw against Georgia at the weekend, and they thought they'd made the perfect start when Shane Duffy converted Robbie Brady's cross from close range but the celebrations were cut short by the offside flag.
Republic of Ireland: Randolph (7), Christie (5), Duffy (6), Clark (6), Ward (6), Meyler (7), Hoolahan (6), Brady (7), Walters (6), McClean (6), Long (6).
Subs: O'Dowda (6), Hourihane (6), Murphy (6).
Serbia: Stojkovic (8), Ivanovic (7), Vukovic (6), Maksimovic (5), Rukavina (6), Kolarov (7), Milivojevic (6), Matic (6), Mitrovic (6), Tadic (7), Kostic (7).
Subs: Mitrovic (6), Gudelj (6), Prijovic (6).
Man of the match: Vladimir Stojkovic
Backed by the home crowd, Republic of Ireland continued to threaten and they went close again in the 20th minute through Shane Long, whose long-range effort was tipped over the bar by Vladimir Stojkovic.
Serbia eventually grew into the game and in the 33rd minute created their first clear-cut opening. Dusan Tadic's pass released Filip Kostic and he pulled the ball back for Aleksandar Mitrovic, but the Newcastle striker's goal-bound effort was clawed away by Darren Randolph.
It was the visitors who were celebrating the 55th minute when Kostic guided the ball perfectly on to the fast-arriving Kolarov's left boot and he thundered it off the underside of the crossbar, leaving Randolph helpless.
Ireland needed a response and O'Neill brought on striker Daryll Murphy to replace Wes Hoolahan with 28 minutes remaining, and the new man made a swift impact.
As he set off in pursuit of Brady's ball over the top, last man Maksimovic slipped and was adjudged to have brought him down, prompting referee Cuneyt Cakir to brandish a red card, although Brady wastefully drilled the resulting free-kick into the defensive wall.
Murphy was convinced he should have been awarded a 76th-minute penalty for a challenge by Jagos Vukovic as he tried to meet substitute Callum O'Dowda's teasing cross, and saw an 86th-minute snapshot palmed away by Stojkovic as the Republic's World Cup dream started to ebb away.
Wes Hoolahan and David Meyler were drafted into the starting line-up in place of Glenn Whelan and Harry Arter. Meanwhile, Serbia coach Slavoljub Muslin made four changes to the team which started the victory over Moldova at the weekend with keeper Vladimir Stojkovic, defenders Jagos Vukovic and Antonio Rukavina and midfielder Luka Milivojevic getting the nod.
- Republic of Ireland lost their first competitive home game under Martin O'Neill, ending a run of nine games without defeat at the Aviva Stadium.
- Overall, they suffered defeat in competitive action at the Aviva Stadium for the first time since September 2013 (v Sweden), under Giovanni Trapattoni.
- Republic of Ireland remain winless against Serbia, with both of their losses coming on home soil (D3 L2).
- Martin O'Neill's side have scored just two goals at home in 2018 World Cup qualifying; only Faroe Islands (1) and Latvia, San Marino and Liechtenstein (all zero) have scored fewer amongst European nations.
- Belgium's Thomas Meunier (4) is the only defender to have scored more goals than Aleksandar Kolarov (2) in 2018 European World Cup qualifying.
- Filip Kostic has assisted three of Serbia's last four goals in this World Cup qualifying campaign.
Man of the Match - Vladimir Stojkovic
Republic of Ireland looked a threat at set pieces all game but Stojkovic stood up to the challenge, commanding his penalty area to great effect.
He also read the play brilliantly and showed excellent handling all night.
He also made what proved to be a crucial save in the 86th minute to deny Murphy, sticking his right boot out to block the substitute's snapshot.
Republic of Ireland, who will be without Robbie Brady and James McClean through suspension, face Moldova at home on Friday, October 6, before finishing their campaign on October 9 with what could be a decisive trip to Cardiff to face Wales.
For Serbia, they can clinch qualification to the World Cup with victory in Austria on October 6 but should they need another game they face Georgia at home three days later.