Aleksandar Kolarov wrecks Republic's World Cup dream with winner in Dublin
Aleksandar Kolarov wrecked the Republic of Ireland's World Cup dream as 10-man Serbia eased themselves to the brink of qualification on a controversial night in Dublin.
Kolarov's 55th-minute piledriver secured a precious 1-0 win at the Aviva Stadium and guaranteed his side a top-two finish in Group D despite defender Nikola Maksimovic's 68th-minute red card.
But Ireland were furious not to be awarded a penalty for Jagos Vukovic's challenge on substitute Daryl Murphy six minutes later as Turkish referee Cuneyt Cakir waved away their appeals.
Martin O'Neill's misery was compounded by Wales' 2-0 victory in Moldova, which means the Republic now sit third in the group with just two games to play and with key men Robbie Brady and James McClean suspended for the Moldovans' visit to the Aviva next month.
On a night when victory was the only real option, Glenn Whelan and Harry Arter paid the price for their side's poor first-half display in Georgia on Saturday as David Meyler and Wes Hoolahan, who had been nursing a groin problem, were drafted in.
O'Neill also opted to tinker with his system, handing Hull midfielder Meyler the task of patrolling the space in front of his back four at the base of a diamond which had creator in chief Hoolahan at its peak, and his boldness was rewarded with a much improved performance.
Hoolahan's talent for finding space and picking out incisive passes invigorated the men around him and Shane Long, who had been fatally isolated in Tbilisi, suddenly found himself in the thick of the action with Jonathan Walters, McClean and Brady able to link with him at regular intervals.
There was an early scare for Ireland when Meyler surrendered possession inside his own penalty area and Shane Duffy had to hurl himself into the path of Nemanja Matic's well-struck drive, but for much of the half, it was the Republic on the front foot.
Central defender Duffy saw a 10th-minute header correctly ruled out for offside after Brady and Hoolahan has worked a short corner move, and Serbia keeper Vladimir Stojkovic was relieved to get his fingertips to Long's stinging 20th-minute effort after Meyler had robbed striker Aleksandar Mitrovic to spark a swift counter-attack.
The group leaders found themselves defending deep for long periods, but their pace on the break was impressive and it had taken a well-timed intervention by full-back Cyrus Christie to deny Mitrovic a clear 14th-minute run on goal.
But as the half wore on, it was wide-man Filip Kostic who caused the problems, linking with Dusan Tadic down the left before pulling the ball back for Mitrovic, whose stabbed 33rd-minute effort was turned away by keeper Darren Randolph.
Kostic supplied the ammunition once again three minutes before the break, but this time wing-back Antonio Rukavina skied his left-foot shot high over.
Ireland were served with a timely reminder of the threat posed by Serbia when Mitrovic cleverly flicked the ball around Newcastle team-mate Ciaran Clark and into the path of Tadic, although his shot lacked both the power and direction to trouble Randolph as Stephen Ward covered across.
Long, the victim of some robust treatment from the Serbian defence, failed to extend Stojkovic as much as he might have after being played into space down the left and cutting across Branislav Ivanovic with 53 minutes gone.
However, it was the visitors who were celebrating within two minutes when Kostic guided the ball perfectly on to the fast-arriving Kolarov's left boot and he dispatched it off the underside of the crossbar with a venom which left Randolph helpless.
It took Ireland some time to regroup and it was not to universal approval that Hoolahan departed to be replaced by striker Murphy 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 Mr 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 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.