Britain's Joel Freeland scores past Poland"s Maciej Lampe
Great Britain's patched-up team lost 70-56 to Poland in their first game of the Game On tournament at the O2 Arena.
Joel Freeland underlined his growing maturity at international level with 16 points and Nick George added 11.
With only 12 fit players due to injuries and other absences, Chris Finch's team coped well for the first 23 minutes and trailed just 35-39.
But Poland then hit 16 points without reply and the closest GB could get to their opponents was 13 points.
Already missing star man Luol Deng, GB were also missing Flinder Boyd, Robert Archibald and Kieron Achara with injury and Andy Betts, who has returned home for personal reasons.
That seemed not to matter in the early stages, with Freeland coping with the threat of Orlando Magic centre Marcin Gortat and George coming off the bench to hit four points in an early 16-9 lead.
I thought our guards played badly tonight
Poland hit back in the second quarter to lead 30-27 at half-time, but it was the third quarter that derailed GB.
They twice failed to inbound the ball properly in Poland's 16-0 run and were punished for handling the ball poorly as Poland effectively secured the game.
Finch was given a rare technical foul for venting his frustration with the officials but was largely unworried by the rustiness of the team's first outing of the summer.
"I thought our guards played badly tonight," he said. "But we're missing a huge chunk of our best players.
"Joel played well - he got more aggressive as the game went on - that's the way we're going to need him to play."
GB take on Turkey, who beat Israel in the tournament's opening game, on Saturday and expect to have Boyd and Achara back for that encounter.
GB small forward Nick George and guard Nate Reinking show the skills and moves needed to make smaller players successful at the top level