Team USA still poses a threat at the FIBA World Cup even if Kemba Walker rather than LeBron James is its marquee player, says former Germany star Demond Greene.

The United States, which has five titles to its name, has seen several world superstars such as James pull out of contention for the tournament that starts on Saturday in China.

But Greene, who played at two World Cups, famously blocking Dwyane Wade in 2006, acknowledges players such as Walker and Khris Middleton could still have a huge impact on the finals.

"It's not their 'A-team'. I would not even say it's their 'B-team'," Greene told Omnisport. "It's a mix between 'B-' and 'C-team'. Despite this, they are still dangerous."

Greene added: "You must never underestimate them. [The players] are still playing in the NBA.

"They've got players who average 20 points per game like Kemba Walker. They are All-Stars and leaders in their teams which proves that they are high quality players.

"The problem is that we are spoiled from the previous years, when players like James Harden, Kevin Durant or LeBron James played.

"Now you have players like Khris Middleton, who many won't even know. You have to be a basketball expert to know Khris Middleton, maybe even Kemba Walker.

"That's the problem, that many look at who's not in the team, rather than who is."

Greece is another potential contender due to the presence of Middleton's Bucks teammate and reigning NBA MVP Giannis Antetokounmpo.

Greene believes the Greeks can be successful but says the team's big European stars must get used to playing second fiddle to Antetokounmpo, who will dominate the narrative.

"The important thing is that all players understand their role," Greene said. "The years in which Giannis didn't play, all the players had another role.

"He is the top star on and off the court. When there are press conferences, there are going to be 50 cameras around him and the other players will get what is left. You have to handle this.

"They have to understand that even if they play a totally different role in Europe and are top stars here, like Nick Calathes at Panathinaikos. He is a team leader there and also still for Greece. He may even be the heart of the team.

"They all have to cope with that. If this works out, then they can get very, very far with Giannis as their power machine.

"But it all has to work out internally and they will have to let him walk in front and let him be the leader with Calathes at his side.

"Then they can be a very dangerous side, especially in defense. Offensively, they are not that strong, but in terms of defense, they can really hurt other teams."