A lot of attention has been paid to the players who won't be at Team USA training camp in preparation for the FIBA World Cup, but the players who are in attendance are grateful for the chance to represent their country.

"This is like a once-in-a-lifetime opportunity for a lot of us," Boston Celtics guard Kemba Walker told reporters in Las Vegas on Monday. "I think a lot of us are happy those guys pulled out because this is our chance.

"It's our chance to get on the big stage and showcase our talent. A chance for us to do something new. It'll be a new-look team. Everybody is kind of doubting us, but I think we're hungry."

The Houston Rockets' James Harden and Eric Gordon, the Portland Trail Blazers' Damian Lillard and CJ McCollum, the Los Angeles Lakers' Anthony Davis and the Washington Wizards' Bradley Beal are among the star players who withdrew from Team USA training camp.

That leaves the Celtics' Walker, Marcus Smart and Jayson Tatum, the Lakers' Kyle Kuzma, the Toronto Raptors' Kyle Lowry, the Milwaukee Bucks' Khris Middleton and the Utah Jazz's Donovan Mitchell among the 15 players on the roster at training camp, which started Monday.

"Obviously, we play with more of a chip [on our shoulders]," Mitchell said, according to the Las Vegas Review-Journal. "I think a lot of countries think they see an opening, so for us we have to go out there and compete and get ready. We're going to get every team's best shot."

Team USA coach Gregg Popovich said he is only worried about the players who are at training camp.

"I've said that we're going to be fine and by that what I really meant is that we're blessed with a lot of depth in USA Basketball," he said. "All of the players here want to be here, there's no question about it. And that's a big part of the battle itself. And so, when you look at the enthusiasm, the youth, the athleticism and versatility, that'll really work well for us because our depth will be a factor.

"These are not 'C' players. You've heard a lot of criticism about who isn't here, and I keep repeating that it's about who is here. There's some really good talent and it's going to be difficult getting to a 12-man roster when you really think about it. So, every day is important to these players and I would say today's effort was terrific. We had a great first day of practice. Certain individuals did an outstanding job. Overall, it was terrific."

The 2019 FIBA World Cup begins in China on Aug. 31. Team USA begins play against the Czech Republic on Sept. 1.