GB will need Luol Deng for European qualifying next year
Great Britain have been passed over for a wildcard for the World Championship and must instead play in next summer's 2011 EuroBasket qualifying programme.
World governing body Fiba instead gave the four available wildcards to Russia, Germany, Lithuania and Lebanon.
Chris Finch's team asked to be allowed to play in the tournament in Turkey as part of their bid to convince Fiba to let them play in the 2012 Olympics.
GB crashed out of EuroBasket 2009 in Poland after three defeats.
However, all three of their group opponents reached the European semi-finals in Katowice.
GB were one of eight nations on Fiba's shortlist for a World Championship wildcard.
"We're still disappointed, obviously," commented GB performance director Chris Spice.
"We tried everything we could to get (the wildcard). The fact that we made it to the last eight is significant in itself."
Although the maximum three wildcards went to Europe, the strong recent pedigree of Germany, Lithuania and Russia made it unlikely that the comparatively new GB programme would be favoured.
Fiba has said Great Britain must prove themselves in order to gain a 2012 Olympic spot but has not made exact criteria public.
GB's case for a wildcard had been backed up by NBA Commissioner David Stern, among others, but it would seem that Fiba need further convincing of the team's competitiveness against European opposition.
Without NBA star Luol Deng, who was ruled out with a stress fracture, GB lost to Slovenia, Spain and Serbia in their three EuroBasket group games in Warsaw in September.
The last thing we want to do is not make it to EuroBasket in 2011. The situation is the same as it was two years ago.
GB Performance Director Chris Spice
Fiba may still have had concerns about GB's strength in depth when it came to making the wild card decision.
"I think the accusation that we're a one-man team is a little unjust," Finch told GB Sport. "Although Luol does bring us an extra dimension across a range of categories."
Spice echoed that, pointing out that Deng was absent when GB came close to pulling off the shock of the tournament against Spain in Warsaw.
Finch pointed out that the team's other NBA player, Pops Mensah-Bonsu, only joined the team in the final week before EuroBasket started.
GB must now await next year's draw for the qualifying competition for the 2011 EuroBasket finals, which will be held in Lithuania.
If that draw - to be held on 16 January - throws up a difficult group, it could mean a setback to GB's hopes of appearing as hosts at the 2012 Olympic tournament.
They will be one of 15 teams in the Euro draw and are likely to be among the second rank of seeds as they bid to reach the finals for the second successive time.
In those circumstances, the presence of Deng could be crucial if the team are to qualify for the 2011 finals.
"There's certainly no question in terms of Luol's commitment - we're expecting him to play," said Spice.
"There's always pressure on us - the last thing we want to do is not make it to EuroBasket in 2011. The situation is the same as it was two years ago and we were qualifying."