Fenerbahçe U19s beat Manchester United U19s 2-0 in the Mercedes Benz Junior Cup second group stage.
The Yellow Canaries took an early lead and then doubled their goal tally in the second half.
United take on Hoffenheim in the second match of Group Two on Sunday 4 January. Fenerbahçe will face Stuttgart in their second game.
The Mercedes Benz Junior Cup is a two-day U19 football tournament setup that has been running for 24 years.
97 teams from 38 different countries have played at in the competition since it was formed in 1991.
87 participants have gone on to become national team players for their respective countries including five World Cup winners this summer: Manuel Neuer, Sami Khedira, Mesut Özil, Benedikt Höwedes and Christoph Kramer.
The 2015 tournament runs from January 3-4 and involves eight teams from five difference countries: Manchester United, Fenerbahçe Istanbul, Celtic Glasgow, Grasshopper Club Zürich, TSG 1899 Hoffenheim (German U-19 champion), VfB Stuttgart, Borussia Mönchengladbach and Schalke 04.