"There are some teams that are stronger than others but anyone can give you a surprise because there are a lot of talented teams and you have to compete really hard, play really hard and concentrate to beat them," Gasol said.

"You have to earn a seat and you can only do it at the end of the championship when you see where you end up as a team."

A field of 24 teams will play five games each over six days in the opening round-robin to decide 16 qualifiers for the knockout stages, the top four from each of four groups advancing.

Saturday's opening round-robin matches in Group D send the Americans against Puerto Rico, China against Italy and Slovenia against Senegal.

Reigning Olympic champion Argentina and France meet in Group A's top game. Two-time defending champion Serbia and Montenegro, a record five-time world champion, will open against Nigeria and Lebanon will face Venezuela.

Australia and Brazil meet to open Group C, which also has Lithuania playing Turkey and Eurobasket 2005 winner Greece against Qatar, while Group B sees the hosts meet Germany while Angola play Panama and the Spaniards meet New Zealand.