Chris Finch's side had pushed hosts Lithuania close less than 24 hours earlier but this was always going to be a stiffer test.
Turkish coach Oehun Ene was complimentary but the gulf in class with evident from early on, with the exception of Britain's Chicago Bulls star Luol Deng, who again top scored with 22 points and contributed eight rebounds in the 90-61 defeat.
"Turkey were excellent and the game was won in the first quarter with their threes and offensive rebounds," said Finch.
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"Im extremely concerned about the fact that we weren't aggressive enough early in the game. I'm surprised we were tentative, we just need to get better.
Britain have long been making positive steps but with next year's Olympics getting closer, they now realise that moral victories are starting to feel hollow.
US-based big man Eric Boateng was particularly scathing about the defeat, claiming more mental toughness is required to compete on back-to-back days.
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