Jon Walters' fifth international goal was not enough to prevent the Republic of Ireland from slipping to a second successive friendly defeat.
The Stoke frontman dragged his side back into it with just 12 minutes remaining after Turkey had taken a 2-0 lead at the Aviva Stadium, but Martin O'Neill's men were unable to rescue themselves as the visitors held out.
Ahmet Ilhan Ozek's first goal for his country handed the Turks a 17th-minute lead, and substitute Osman Tarik Camdal ultimately secured victory with 14 minutes from time.
Ireland, playing in front of a sparse crowd - one dwarfed by the attendance at Croke Park for boyband One Direction's concert the same evening - played in fits and starts with wingers Aiden McGeady and James McClean and playmaker Wes Hoolahan the bright spots.
They might have been awarded two penalties as Turkey defender Omer Toprak rode his luck, and the visitors were indebted to the resilience of goalkeeper Onur Recep Kivrak.
However, the Republic were unable to convert possession into goals and paid the price as Fatih Terim's side matched Serbia's feat in March by winning in Dublin.
The challenge now increases significantly for O'Neill and his players as they face World Cup-bound Italy, Costa Rica and Portugal - all of whom are ranked higher than the Turks by FIFA, in their remaining summer fixtures.
O'Neill rewarded Newcastle goalkeeper Rob Elliot for his commitment - the 28-year-old missed his own stag trip to Las Vegas to join up with the squad - by handing him a first senior cap.
The Newcastle man had little time to settle as he was called upon for the first time with less than a minute gone to keep out striker Mevlut Erdinc's skidding shot, and, but for a near-post block by Stephen Ward, he might have been required once again seconds later.
However, it was Ireland who largely enjoyed the better of the opening stages, and they were hugely aggrieved not to be awarded a fifth-minute penalty after Shane Long went down under Toprak's clumsy challenge, but not to the satisfaction of French referee Ruddy Buquet.
Ward smashed a left-footed shot just wide of the far post two minutes later with the home side in enterprising mood, and Long was denied by Onur from point-blank range before John O'Shea's follow-up was blocked on the line.
But the home side were to be felled by a sucker punch with 17 minutes played.
Gokhan Gonul's right-wing cross was inviting, but the header applied to it by Ahmet proved unstoppable as Elliot dived full length to no avail.
Ireland's response was concerted, with McGeady the architect of much of their best work.
He led full-back Caner Erkin a merry dance to produce a series of dangerous balls into the box, one of which was headed wide by McClean.
The Wigan midfielder turned provider 10 minutes before the break with a cross which Long back-heeled just off target, and he was unfortunate not to level himself within seconds when Onur repelled his well-struck shot from McGeady's left-wing cross.
Neither side was able to exert any real control in a scrappy start to the second half with play largely confined to the middle third of the pitch.
However, Hoolahan sparked Ireland back into life with a raking 59th-minute crossfield pass which McGeady controlled expertly before seeing his shot blocked at source by Erkin.
But there was action too at the other end of the pitch with Damien Delaney twice having to block Erdinc shots, the second of them a piledriver from distance, within three minutes.
The Crystal Palace defender departed three minutes later along with McGeady and Long as O'Neill introduced David Meyler, Daryl Murphy and Walters with Marc Wilson, who had started the game in central midfielder, dropping into the back four as a result.
Turkey dropped ever deeper as the Republic made their big push with Hoolahan orchestrating behind the front two of Walters and Murphy, and Toprak was fortunate to escape once again after appearing to tug Hoolahan's shirt inside the box with 15 minutes remaining.
Ireland were still smarting when their fortunes dipped further as substitutes Oguzhan Ozyakup and Tarik combined for the later to extend the visitors' lead in emphatic style just seconds later.
Walters' equally convincing finish after wrong-footing Toprak later gave O'Neill's men hope, but Murphy headed straight at Onur from McClean's 86th-minute cross as the Republic came up short.