Roberto Mancini's return to Galatasaray ended in a 1-0 defeat as Wesley Sneijder proved the match-winner against former club Inter.
Wesley Sneijder struck the only goal of the game to earn Galatasaray a 1-0 friendly win over his old club Inter on Sunday.
The Netherlands international spent four years at the Serie A club between 2009 and 2013, winning the treble of league, Coppa Italia and UEFA Champions League under Jose Mourinho in 2010.
And it was Sneijder's effort that ensured Inter coach Roberto Mancini endured a losing return to Gala, whom he managed during the 2013-14 campaign.
Sneijder was set up by Lukas Podolski - who spent the second half of last season on loan at Inter - as the visitors fell to their fourth successive pre-season defeat, all without scoring.
Stevan Jovetic, fresh from completing a move from Manchester City, made his Inter debut as a second-half substitute, but the Montenegro international was unable to conjure up a response for his new employers.
Inter still have three weeks until their Serie A campaign gets under way, while Gala's season begins in earnest next weekend, when they face Bursaspor in the Turkish Super Cup.
The home side ought to have gone ahead in the fifth minute but Podolski fired into the legs of Samir Handanovic from eight yards.
Gala thought they had made the breakthrough shortly afterwards when Handanovic spilled Selcuk Inan's long-range effort and Burak Yilmaz converted the rebound, only for the officials to rule the striker had used a hand in bundling the ball home.
At the other end, Mauro Icardi shot weakly at Fernando Muslera when clean through as the open nature of the contest continued.
Nine minutes into the second half, Gala edged ahead as two former Inter men combined.
Podolski got away from Inter debutant Miranda down the left and cut the ball back for Sneijder, who had time and space to take a touch and fire low past Handanovic at his near post.
The hosts went agonisingly close to a second on the hour when substitute Sinan Gumus fired narrowly wide of the left-hand upright.
A scramble in the Gala box caused panic wth four minutes remaining, but Martin Montoya's snatched effort was straight at Muslera and Inter's last chance to salvage a draw was wasted.